43+ CPP Decimal to Binary Converter Programs

This post Contains a total of 43+ CPP Decimal to Binary Converter Program Examples with Source Code. All these Decimal to Binary converters are made using C++ Programming Language.

You can use the source code of these examples with credits to the original owner.

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CPP Decimal to Binary Converter Programs

1. By Harsh Kumar

Made by Harsh Kumar. Enter decimal number to get binary number. Source

Decimal number:
10
After conversion
Binary number:
1010
#include <iostream>
using namespace std;

int main() {
long int dec,red[100],quo,i=1,j;
cin>>dec;
quo=dec;
if(quo<0)
{
    cout<<"Not Possible Conversion";
}
else if(quo==0)
{
 cout<<"Decimal number:\n"<<dec;
 cout <<"\nAfter conversion";
 cout <<"\nBinary number:\n"<<quo; 
}
else
{
while (quo!=0)
  {
      red[i]=quo%2;
      quo=quo/2;
      i++;
  }
 cout<<"Decimal number:\n"<<dec;
 cout <<"\nAfter conversion";
 cout <<"\nBinary number:\n";
for (j=i-1;j>0;j--)
{
    cout<<red[j];
}
    return 0;}
}

2. By Yoshideveloper

Made by Yoshideveloper. Simple C++ Program to Convert Decimal number to binary. Source

The binary form of 11 is 1011

#include<iostream>
using namespace std;

void binary(int num)
{
    int rem;

    if (num <= 1)
    {
        cout << num;
        return;
    }
    rem = num % 2;
    binary(num / 2);
    cout << rem;
} 

int main()
{
    int dec, bin;
    cin >> dec;

    if (dec < 0)
        cout << dec << " is not a positive number." << endl;
    else
    {
        cout << "The binary form of " << dec << " is ";
        binary(dec);
        cout << endl;
    }
    return 0;
}

3. By Babak

Made by Babak. A simple base converter from Dec to Bin and capable to handle NEGATIVE decimals to produce 2’s complement. Source

12 = 
0000 0000 0000 0000 0000 0000 0000 0000 
0000 0000 0000 0000 0000 0000 0000 1100
/* Code name: 
 * By : Babak Sheykhan (Pers)
 * Date : Aug 1, 2017
 * /////////////////////////////////////////////////
 * Change log #1 (v.0.02) - Aug 2, 2017
 *
 * 1. Converting to Hexadecimal added
 * 2. Solve some minor bugs
 *
 * /////////////////////////////////////////////////
 * Change log #2 (v.0.03) - Aug 29, 2017
 * [** Special thanks to my mentor JPM7 for his guidance and positive feedbacks **]
 *
 * 1. Optimizing the code using bitwise and shift operator.
 * 2. Easier to read binary in output
 *
 */

#include <iostream>
#include <vector>
#include <string>
#include <climits> // CHAR_BIT
using std::cout; using std::cin; using std::endl;

// Prototypes
bool isDec(long long d);
void converter(long long d, std::vector<int> &vHex);

int main() {
    cout << "NOTE: Numbers greater than 9,223,372,036,854,775,807  and\n"
        "      less than -9,223,372,036,854,775,807 are Invalid.\n\n";
    /*---- Hex Memory ----*/
    std::vector<int> memHex(16, 0); 
    /*---- Holds Decimal ----*/
    long long dec = 0;
    
    /**** Input eval loop ****/
    do {
        cout << "Enter a positive or negative decimal number: ";
        cin >> dec;
    } while (!isDec(dec));

    cout << "\nConverting to binary and hexadecimal...\n\n";
    cout << dec << " = \n";
    converter(dec, memHex);
}

bool isDec(long long d) {
    /**** Error Handling ****/
    // Handling Non-numeric and too long input
    if (std::cin.fail()) {
        std::cin.clear();
        std::cin.ignore(200, '\n');
        cout << "Invalid input!\n";
        return false;
    }
    else return true;
}

void converter(long long d, std::vector<int> &vHex)
{
    //if (d < 0) ~d; // ! DUMB MISTAKE !

    std::string lookupHex = "0123456789ABCDEF";
    short lookupPow[]     = {8, 4, 2, 1};
    const int Shift       = CHAR_BIT * sizeof(long long);
    const long long Mask  = 1LL << (Shift - 1);
    int x                 = 0; // index of vHex

    for (int i = 1; i <= Shift; ++i) {
        cout << (d & Mask ? 1 : 0);
        vHex[x] += lookupPow[(i-1)%4] * (d & Mask ? 1 : 0);
        if (i % 4 == 0) {
            ++x;
            cout << " ";
            if (i % 32 == 0) cout << endl;
        }
        d <<= 1;
    }
    cout << endl;
    for (size_t j = 0; j < vHex.size(); ++j) cout << lookupHex[vHex[j]];
    cout << endl;
}

4. By Sololearn

Made by Sololearn. Source

10011100
#include <iostream>
using namespace std;
/* A binary number is made up of elements called bits where each bit can be 1 or 0 */
string binary(int);

int main() 
{
    //sample number
	int number = 156;
	
	cout << binary(number);
	
	return 0;
}

string binary(int num) {
    string bin;
    char holder=' ';
    while(num != 0)
    {
        holder = num %2 + '0';
        bin = holder + bin;
        num /= 2;
    }
    return bin;
}

5. By DONALSOFT

Made by DONALSOFT. Source

Enter a decimal integer to convert it to octal and binary 
Input number is = 13

It's Octal equivalent is = 15
It's binary equivalent is = 1101
#include <iostream>
using namespace std;

int main() {
     /***************************DONALSOFT**************************/
     /******************DECIMAL TO OCTAL AND BINARY******************/     
     long num, decimal_num, remainder, base = 1, octal = 0, binary = 0;
     long bdecimal_num, b_remainder, b_base = 1;
     cout<<"Enter a decimal integer to convert it to octal and binary "<<endl;
     cin>>num;
     bdecimal_num = num;
     decimal_num = num;
     while(num > 0){
         remainder = num % 8;
         octal = octal + remainder * base;
         num = num / 8;
         base = base * 10;
     }
     
     while(bdecimal_num > 0){
         b_remainder = bdecimal_num % 2;
         binary = binary + b_remainder * b_base;
         bdecimal_num = bdecimal_num / 2;
         b_base = b_base * 10;
     }
     cout<<"Input number is = "<<decimal_num<<endl;
     cout<<""<<endl;
    cout<<"It's Octal equivalent is = "<<octal<<endl;
     cout<<"It's binary equivalent is = "<<binary<<endl;
    
    return 0;
}

6. By Janusz Bujak

Made by Janusz Bujak. Source

14 -> 1110
#include <iostream>
using namespace std;

long bin(long n) {
    return n>0 ? n%2+10*bin(n/2) : 0;
}

int main() { 
    long n;
    cin >> n;
    cout << n << " -> " << bin(n);
}



/*
cout << bin << 999;
cout <<" oct "<< oct << 999;
cout <<" dec "<< dec << 999;
cout <<" hex "<< hex << 999;
*/

7. By Arnav

Made by Arnav. Source

Enter a number:15 
Binary number: 1111
#include <iostream>
using namespace std;

int main() {
    cout << " Enter a number: ";
    int n;
    cin >> n;
    string b = "";
    do
    {
        if (n % 2 == 1)
            b = '1' + b;
        if (n % 2 == 0)
            b = '0' + b;
        n /= 2;
        
    }while (n != 0);
    
    cout << endl << " Binary number: " << b;
    return 0;
}

8. By RJ

Made by RJ. Source

Enter the number to convert
16
Binary of the given number=10000
#include <iostream>
using namespace std;

int main() 
{
int a[10],n,i;
cout<<"Enter the number to convert";
cin>>n; 
for(i=0;n>0;i++)
{
  a[i]=n%2;
  n=n/2;
 }
cout<<"Binary of the given number=";
for(i=i-1;i>=0;i--)
{
cout<<a[i];
}
return 0;
}

9. By AliRΰ«―za

Made by AliRΰ«―za. Source

17
17 in binary : (10001)
#include <iostream>
using namespace std;
int main()
{
    int bin[1000],num,x;
    cin>>num;
    cout<<num;
    for(;;x++)
    {
        bin[x]=num%2;
        num/=2;
        if(num==1)break;
    }
    cout<<" in binary : ("<<1;
    for(;x>=0;x--)cout<<bin[x];
    cout<<")";
}

10. By ApidBoy

Made by ApidBoy. This C++ Program Simply Converts Decimal Numbers Into Binary, STEPS TO USE: Simply Just Enter The Number And Run The Code You’ll Get Its Binary Conversion! Source

18
The Binary Conversion Of The Number 18 Is: 10010

#include<iostream>
using namespace std;
int main()
{
    int arr[15];
    int n;
    cin>>n;
    cout<<"The Binary Conversion Of The Number "<<n<<" Is: ";
    int j=0;
    while(n>0){
    arr[j++]=n%2;
    n=n/2;
    }
    for(int i=j-1;i>=0;i--){
    cout<<arr[i];
    }
}

11. By Kinshuk Vasisht

Made by Kinshuk Vasisht. Source

Number Entered        - 
19

Memory Representation - 
00000000000000000000000000010011

Binary Representation - 
10011

//Input  - Any decimal number .
//Output - Their binary representations.

#include <iostream>
 // cout, cin
#include <string>
   // string
#include <cmath>    // floor, ceil

#include <bitset>
// Header containing a class to store binary
// representations of types (anything, even 
// classes),using a vector<bool>.
// Each bool variable stores the state of 
// the bit, whether its a 1 or a 0.

#include <typeinfo>
// Header containing data on types. Useful 
// for type comparison at compile time.

#define sub substr
using namespace std;

bool isint(float a)
 // Checks if a is an int.
{
 return (floor(a)==ceil(a));
 }

string fw(string num)
// Erases extra zeroes from the beginning.
{
    num.erase(0,min(num.find_first_not_of
    ('0'),num.size()-1));
 return num;
}

string rv(string num)
// Erases extra zeroes from the end.
{
    num.erase(num.find_last_not_of('0')+1,
    num.size()-1); return num;
}

template<typename T>
 string convert(T a)
/// Function to convert number to binary.
{
    bitset<(sizeof(T)*8)> bin
    = *(reinterpret_cast<int*>(&a));

    // The bitset object is created by
    // specifying the size of bits you need
    // to see the number completely.

    // Since we are working with bits, the
    // best size will be the size ofthat
    // class, multiplied by 8.
    // (1 byte = 8 bits)

    // The reinterpret_cast converts
    // the variable to the form in which 
    // it is stored in memory. This is used 
    // to create the binary representation.

    string res = bin.to_string();

    /// We then convert the binary number to
    /// a std::string for use.

    return res;
}

int revert(string bin, int bias = 0)
/// Converts a binary string to decimal.
{
    int a = stoi(bin,nullptr,2);
    a -= bias;
 return a;
}

template<typename T>
 void Print(T num)
///Utility to Print Binary Representation.
{
    cout<<"Number Entered        - \n"
        <<num<<endl<<endl;
    if( typeid(T)==typeid(float)    ||
        typeid(T)==typeid(double)   ||
        typeid(T)==typeid(long double))
    // If we received a float as the argument
    {
        int exp=0,man=0,bias=0,exv;
        if(typeid(T)==typeid(float)) 
        {exp = 8; bias = 127;}
        if(typeid(T)==typeid(double)) 
        {exp = 11; bias = 1023;}
        if(typeid(T)==typeid(long double)) 
        {exp = 15; bias = 16383;}
        man = (sizeof(T)*8)-exp-1;
        
        string res = convert(num),mant;
        exv = revert(res.substr(1,exp),bias);
        cout<<"Memory Representation - \n";
        cout<<res<<endl<<endl;
        
        // The above part of the code 
        // decides the number of bits to 
        // count for mantissa and exponent,
        // which are combined with a sign bit
        // to form the IEEE754 representation
        // of floating-point numbers.
        // The number of bits vary for float,
        // double, and long double.
        // The bias was added to exponents to
        // keep the exponent > 0.

        cout<<"Binary Representation - \n";
        mant = "1"+res.sub(exp+1,man);
        if(exv>0) mant = mant.sub(0,exv
                  +1)+"."+mant.sub(exv+1,
                  mant.size()-exv-2);
        else if(exv==0) mant = mant.sub
        (0,1)+"."+mant.sub(1,mant.size()-1);
        else 
{
 for(int i=0;i<abs(exv)-1;i++) 
           mant="0"+mant;
 mant = "0."+mant; 
}
       
        cout<<(res[0]=='0'?"":"-")<<rv(mant);
        
        // The binary form of the float is 
        // calculated by prefixing a 1 to the
        // mantissa, and then moving the 
        // decimal point from the original 
        // position, before the mantissa,
        // to the final position as indicated
        // by the exponent.
        
        cout<<"\n\nSign     - "<<(res[0]=='0'
        ?"Positive (+)\n":"Negative (-)\n");
        cout<<"Exponent - "<<res.sub(1,
        exp)<<" (with a bias of "<<bias
        <<")"<<endl;
 cout<<"Mantissa - "
        <<res.sub(exp+1,man)<<endl<<endl;
    }
    else 
 // Otherwise, continue for integer.
    {
        cout<<"Memory Representation - \n"
            <<convert(num)<<endl<<endl;
        cout<<"Binary Representation - \n"
        <<(num<0?"-":"")<<fw(convert
        (abs(num)))<<endl<<endl;
    }
    cout<<endl;
}

int main()
{
    union{int v2; float v1;} data;
    float num; cin>>num;
 
    if(cin.fail()) num = 26.2; // Default 
    if(!isint(num)) // Case of float.
    { data.v1=num; Print(data.v1); }
    else            // Case of int.
    { data.v2=num; Print(data.v2); }
}

12. By ROHIT KANOJIYA

Made by ROHIT KANOJIYA. Source

20
Binary Converstion of 20 : 10100
#include <iostream>
using namespace std;
/*
 This Code Convert Decimal Number into Binary Number.
 For Example:
 Input: 10
 Output:1010
*/
void DecimaltoBinary(int);
int main()
{
 int num,n;
 cin>>num;

 cout<<"Binary Converstion of "<<num<<" : ";  
 n=num;
 if(num<=0){
  if(num==0)
   cout<<"00000000";
  else
   cout<<"Enter Positive Number: ";
 }
 else
  DecimaltoBinary(n);
 return 0;
}
void DecimaltoBinary(int n)
{
 int rem;
 if(n==0)
  return;
 else{
  rem=n%2;
  DecimaltoBinary(n/2);
  cout<<rem;  
  }
}

13. By RozeS

Made by RozeS. Source

DECIMAL :: 21
BINARY ::  10101
*****************************
#include <iostream>
using namespace std;

//🌷🌷🌷 Enter any decimal Number 🌷🌷🌷//

int main() {

   long n , dec_n , rem , base=1 , bin=0;
   //cout<<"enter a decimal\n\n";
   cin>>n;
   dec_n=n;
   while(n>0){
   rem=n%2;
   bin = bin+rem*base;
   n = n/2;
   base = base*10;
   }
   cout<<"DECIMAL :: "<<dec_n<<"\n";
   cout<<"BINARY ::  "<<bin<<"\n";
   cout<<"*****************************\n";
   cout<<"Thank You :)";
   return 0;
}

14. dρlυѕρlΟ…Ρ•

Made by dρlυѕρlΟ…Ρ•. Type in a decimal number and it will be converted to binary. Source

Decimal number: 22
Binary number: 0000 0000 0001 0110 
#include <iostream>
using namespace std;

int main() 
{
    
        short dec;
        bool tmp;

        cout << "Decimal number: ";
        cin >> dec;
        
        cout << "\nBinary number: ";
        for (int i=1; i<=16; i++)
        {
            tmp= (dec&0x8000) !=0;
            cout << tmp ;
            dec <<=1;
            if (i%4==0)
                cout << " ";
           
        }
        
        cout << endl;
    
    
    return 0;
}

15. By Saksham Saxena

Made by Saksham Saxena. Source

Please enter only two digit number 
 
Enter the decimal to be converted:23
The binary of the given number is:10111
#include <iostream>
 using namespace std; 
 int main() { 
cout << " This converter is made by Saksham Saxena \n ";
cout <<   " Please enter only two digit number \n \n \n";
 long dec,rem,i=1,sum=0; 
  cin>>dec; 
   cout<<"Enter the decimal to be converted:"<< dec<<endl;
  do { rem=dec%2; sum=sum + (i*rem); 
  dec=dec/2; i=i*10; 
  }
  while(dec>0); 
  cout<<"The binary of the given number is:"<<sum<<endl;
   cin.get();
    cin.get();
    cout << "Please upvote if you like it !!! \n \nTHANK YOU :) ";
     return 0; 
     }

16. By Shimon

Made by Shimon. Source

24
11000
#include <iostream>
using namespace std;

long long int B(long long int N){
    long long int A;
    if(N < 1){
    return 0;
    }
    A = N % 2;
    B(N / 2);
    cout << A;
}

int main() {
    long long int D;
    cin >> D;
    B(D);
    return 0;
}

17. By Rishu Kumar

Made by Rishu Kumar. Enter the number to be converted in binary form as input Source

Number entered: 25
Binary form : 11001

#include <iostream>
using namespace std;

int main() 
{
   int x;
   cin>>x;
   int a[100];
   int r; int n=x;
   int i=0; int d=0;
  
   while(n!=0)
   {
       r=n%2;
       a[i]=r;
       n=n/2;
       i++; d++;
   }
   i--;
   int b[100];
   int j=0; 
   while(j<d)
   {
       b[j]=a[i];
       j++;
       i--;
   }
   
   cout<<"Number entered: "<<x<<endl;
   cout<<"Binary form : ";
   i=0;
   while(i<d)
   {
       cout<<b[i];
       i++;
   }
   
   
    return 0;
}

18. By GTimo

Made by GTimo. Input: Any decimal number from 0 – 255 Output: The number converted to an 8 bit binary number. Source

26
00011010
#include <iostream>
#include<iomanip>

using namespace std;


int main() {
    int d1,d2,d3,d4,d5,d6,d7,d8,num;
    cin>>num;
    d8 =num % 2;
    num = num /2;
    d7 =num % 2;
    num = num /2;
    d6 =num % 2;
    num = num /2;
    d5 =num % 2;
    num = num /2;
    d4 =num % 2;
    num = num /2;
    d3 =num % 2;
    num = num /2;
    d2 =num % 2;
    num = num /2;
    d1 =num % 2;
    cout<<d1<<d2<<d3<<d4<<d5<<d6<<d7<<d8;
return 0;
}

19. By Eligijus Silkartas

Made by Eligijus Silkartas. Source

enter a non negative integer
27
11011
#include <iostream>
using namespace std;

int main() {
    int dec;
    
    cout << "enter a non negative integer\n";
    cin >> dec;
    
    if(cin.fail()) {
        cout << "are you sure that's a number?";
        
        return 1;
    }
    if(dec < 0) {
        cout << "program does not work with negative numbers... yet!";
        
        return 1;
    }
    
    // string for binary digits
    string bin = "";
    
    // check how many binary digits there will be
    int i = 1;
    while(dec >> i > 0)
        i++;
    
    // start forming string
    while(dec != 0) {
        if(dec - (1 << --i) >= 0) {
            bin += '1';
            dec -= (1 << i);
        }
        else {
            bin += '0';
        }
    }
    
    // add 0's for remaining digits if needed
    while(i-- != 0)
        bin += '0';
    
    cout << bin;

    return 0;
}

20. By kellouche dhiya

Made by kellouche dhiya. Source

the valeu of number is : 28

binary is : 011100


#include <iostream>
#include <math.h>
using namespace std;


// binary calcule function
unsigned long long int binary_calcule (int num) {
    int j = 0;
    unsigned long long int rusalt = 0;
    
    if(num < 0)
        num *= -1;
    
    while(num) {
        rusalt += (num % 2) * pow(10, j++);
        num /= 2;
    }
    
    return rusalt;
}


// STDOUT message fuction
void message_result(unsigned long long int rusalt,int num) {
    cout << "the valeu of number is : " << num << endl << endl << "binary is : " << (num >= 0 ? 0 : 1)  << rusalt << endl << "the first bit on the left represente the number sign " << endl << "if 1 means the number is negative else the number is positive" <<endl << endl << (num >= 0 ? "in this case the number is positive" : "in this case the number is nigative");
}


// main function
int main() {
    int long DecimalNumber;
    cin >> DecimalNumber;
    
    unsigned long long int sort {binary_calcule(DecimalNumber)};
    message_result(sort, DecimalNumber);
    return 0;
}

21. By SRUSHTI BUCH

Made by SRUSHTI BUCH. Source

Enter Decimal Number 29
For Given Decimal 29 The Binary Form is: 
11101
#include <iostream>
using namespace std;

int main() {

    int d,a,i,b[10],l=0;
    
    cout<<"Enter Decimal Number"<<endl;
    
    cin>>d;
    
    a=d;
    
    for(i=0; (d!=(d%2)); i++){
           b[i]=(d%2);
           d=(d/2);
           l++;
     }
    if(a==0)
       b[i]=0;
  else
      b[i] =1;    
    
    cout<<"For Given Decimal "<<a<<" The Binary Form is: "<<endl;

    for(i=l;i>=0;i--){
        
        cout<<b[i];
    }


    return 0;
}

22. Shivangi Gupta

Made by Shivangi Gupta. Source

Enter the number : 30
The binary of 30 is 11110
#include<iostream>
using namespace std;

void bin(int n)
{
    int rem;

    if (n<= 1)
    {
        cout << n;
        return;
    }
    rem = n % 2;
    bin(n/ 2);
    cout << rem;
}

int main()
{
    int d;
    cout << "Enter the number : \n";
    cin >> d;

    if (d < 0)
        cout << "Enter the positive number"<< endl;
    else
    {
        cout << "The binary of " << d<< " is ";
        bin(d);
    }
    return 0;
}

23. By Amar Dahake

Made by Amar Dahake. Source

31
11111
#include <iostream>
using namespace std;

int main() {
    int num;
    int bin[100];
    int i=0;
    cin>>num;
    while(num)
    {
        bin[i]=num%2;
        num=num/2;
        i++;
    }
    i -=1;
    while(i>=0)
    {
        cout<<bin[i];
        i--;
    }
    return 0;
}

24. By Vaneela Khatri

Made by Vaneela Khatri. Source

32
100000
#include <iostream>
using namespace std;

int main() {
int dec;
cin>>dec;
unsigned int  bi;
int base=1,rem=0;
while (dec){
    rem=dec%2;
    bi+=rem*base;
    dec/=2;
    base*=10;
}
cout << bi;
    return 0;
}

25. By Carlos Castro

Made by Carlos Castro. Source

Enter a decimal integer
Input number is=33
Its binary equivalent is=100001
#include <iostream>
using namespace std;

int main() {
    long num, decimal_num, remainder, base = 1, binary = 0;
    
    cout<<"Enter a decimal integer\n";
    cin>>num;
    decimal_num = num;
    while(num>0) {
        remainder = num % 2;
        binary = binary + remainder * base;
        num = num / 2;
        base = base * 10;
    }
    cout<<"Input number is="<<decimal_num<<"\n";cout<<"Its binary equivalent is="<<binary<<"\n";
    return 0;
}

26. By Med Arezki

Made by Med Arezki.Basic Decimal to Binary Program. Source

34 to binary :100010
#include <iostream>

using namespace std;

int main()
{
    int n(0),nC,a(0),m(1),nR(0);cin>>n;nC=n;
    do{a=nC%2;nR+=a*m;m*=10;nC/=2;}while(nC!=0);
    cout<<n<<" to binary :"<<nR<<endl;
//Nice challenge
return 0;
}

27. By Kai

Made by Kai. C++ Program for Decimal to Binary Conversion. Source

input no. is =35
its binary digit is =100011
#include <iostream>
using namespace std;

int main() {
    long n,dn,r,b=1,binary=0;
    cin>>n;
    dn=n;
    while (n>0){
        r=n%2;
        binary=binary+r*b;
        n=n/2;
        b=b*10;
    }
    cout <<"input no. is ="<<dn<<endl;
    cout <<"its binary digit is ="<<binary;
    return 0;
}

28. By Victor

Made by Victor. Source

enter a no:36
100100
#include <iostream>
using namespace std;
 //Compiler version g++ 6.3.0
 void binary(int num)
{
    int rem;
 
    if (num <= 1)
    {
        cout << num;
        return;
    }
    rem = num % 2;
    binary(num / 2);
    cout << rem;
}

 int main()
 {
 	int b;
 cout<<"enter a no:";
 	cin>>b;
 	binary(b);
 	return 0;
 }

29. By STRIKER

Made by STRIKER. C++ Decimal to Binary Converter using Recursive. Source

Enter a decimal number 37
Binary equivalent of 37 is 100101
#include <iostream>
using namespace std;
int binary(int n){
if (n>1)
binary(n/2);
cout<<n%2;
}

int main() {
int decimal;
cout <<"Enter a decimal number";
cin>>decimal;
cout <<"Binary equivalent of "<<decimal<<" is ";
binary(decimal);
    return 0;
}

30. By Sachin

Made by Sachin. Source

38
Binary equivalent is : 1 0 0 1 1 0 
#include<iostream>
using namespace std;
int main()
{
double n,s[100];
int flag=0,i=0,m,a[100],k,j;
cin>>n; m=n;
do{ a[i++]=k=m%2;
}while(m=(m/2));
cout<<"Binary equivalent is : ";
for(i--;i>=0;i--) cout<<a[i]<<" ";
k=i=0;
m=n;
do{
i++;
n-=m;
if(!n) break;
else
{ if(i==1) cout<<". "; }
n*=2;
for(j=0;j<i-1;j++) if(s[j]==n) flag=1;
s[k++]=m=n;
cout<<m<<" ";
}while(flag!=1);
return 0;
}

31. By Kawaii

Made by Kawaii. Source

Enter the decimal number 39
The number in binary is --> 00100111
#include <iostream>
#include <string>
using namespace std;
int main() {
	cout << "Enter the decimal number" << endl;
	int number, b;
	string binary = "";
	string rbinary;
	cin >> number;
	while (binary.length() < 8) {
		b = number % 2;
		number /= 2;
		binary += to_string(b);
	}
	for (int i = binary.length(); i >= 0; i--) {
		rbinary += binary[i];
	}
	cout << "The number in binary is --> " << rbinary << endl;
	return 0;
}

32. By Wave Stuff

Made by Wave Stuff. Set to handle decimals from 0 to 65,535. If you want larger numbers just change the len variable to your desired length. Source

Decimal: 40
Binary : 0000000000101000
#include <iostream>
#include <bitset>
#include <string>

using std::bitset;

const unsigned len = 16;

int main() {

	unsigned long d;
	
	std::cin >> d;
	std::cout << "Decimal: " << d << "\n";
	
	std::string b = bitset<len>(d).to_string();
	std::cout << "Binary : " << b;
	
	return 0;
}

33. By TerrIA

Made by TerrIA. Source

41
001010
#include <iostream>
using namespace std;

int main() {
    int bin,r[1000],q,i=0,j,k;
    cin >> q;
    bin = q;
    for (k = 0; bin > 0; k++){
        bin = bin/2;
        r[i] = bin%2;
        i++;
    }
    for(j = 0; j < i; j++){
        cout << r[j];
    }
}

34. By Imtinan Abbas

Made by Imtinan Abbas. Source

Enter the number: 42
The binary form of 42 is 101010
#include<iostream>
using namespace std;

void binary(int num)
{
    int rem;
    

    if (num <= 1)
    {
        cout << num;
        return;
    }
    rem = num % 2;
    binary(num / 2);
    cout << rem;
}

int main()
{
    int dec, bin;
    cout << "Enter the number : ";
    cin >> dec;

    if (dec < 0)
        cout << dec << " is not a positive integer." << endl;
    else
    {
        cout << "The binary form of " << dec << " is ";
        binary(dec);
        cout << endl;
    }
    return 0;
}

35. By pur80a

Made by pur80a. Source

please insert your favorite number
decimal:43
binary:101011
/*this code converts decimal into binary numbers
INPUT: Your favorite number
feel free to like*/ 

#include <iostream>
#include <vector>
using namespace std;

int main() {
 int dec,bin;
 cout<<"\t~<<DIGITALIZER>>~\n";
 cout<<"converts decimal number into binary\n\n";
 cout<<"please insert your favorite number\n";
 cin>>dec;
 //dec=11;
 int help{dec};    //dec copied to help variable 
 vector<int> v;    //maybe string would have been better
 while(help!=0){
     v.insert(v.begin(),help%2);     //writes 1or0 into vector
     help/=2; // equivalent to help=help/2
 }
 cout<<"decimal:"<<dec<<endl;
 cout<<"binary:";
 for(int i=0; i<v.size();i++){        //prints vector 
    cout<<v.at(i);
 }
    return 0;
}

36. By Bibaswan Roy

Made by Bibaswan Roy. Source

44
The binary expression of 44 is 101100
#include <iostream>
using namespace std;

int main() {
  int num, i = 1, j;
  long long int bina = 0;
  cin >> num;//enter the positive integer
  int c = num;
  if (num < 0){cout << "Please enter a positive integer";}
  else{
  while (num > 0){
      j = num % 2;
      bina = bina + (j * i);
      i *= 10;
      num /= 2;
      }
  cout << "The binary expression of " << c <<" is "<<bina;}
    return 0;
}

37. By HBKarachi

Made by HBKarachi. Source

Enter a decimal number: Step 1: 45/2, Remainder = 1, Quotient = 22
Step 2: 22/2, Remainder = 0, Quotient = 11
Step 3: 11/2, Remainder = 1, Quotient = 5
Step 4: 5/2, Remainder = 1, Quotient = 2
Step 5: 2/2, Remainder = 0, Quotient = 1
Step 6: 1/2, Remainder = 1, Quotient = 0
45 in decimal = 101101 in binary
#include <iostream>
#include <cmath>
using namespace std;

long long convertDecimalToBinary(int);

int main()
{
    int n, binaryNumber;

    cout << "Enter a decimal number: ";
    cin >> n;
    binaryNumber = convertDecimalToBinary(n);
    cout << n << " in decimal = " << binaryNumber << " in binary" << endl ;
    return 0;
}

long long convertDecimalToBinary(int n)
{
    long long binaryNumber = 0;
    int remainder, i = 1, step = 1;

    while (n!=0)
    {
        remainder = n%2;
        cout << "Step " << step++ << ": " << n << "/2, Remainder = " << remainder << ", Quotient = " << n/2 << endl;
        n /= 2;
        binaryNumber += remainder*i;
        i *= 10;
    }
    return binaryNumber;
}

38. By Silver Key

Made by Silver Key. Source

plz enter decimal no.: 46

46 in binary = 0 0 0 0 1 0 1 1 1 0 
/*

this program convert a decimal number
in range 0 to 1023 .. into binary :)

*/

#include <iostream>
#include <cmath>

using namespace std;

int main() 
{
 int num,n,arr[]={0,0,0,0,0,0,0,0,0,0};
 cout <<"plz enter decimal no.: \n\n";
 cin >> num;
 n = num;
 
 for (int i=9; i>=0; i--)
 {
    if(pow(2,i) <= num)
    {
    num = num - pow(2,i);
    arr[i] = 1;
    }
 }
 cout << n << " in binary = ";
 for (int i=9; i>=0; i--)
 {
    cout << arr[i] << " ";
 }
 cout << endl;
 return 0;
}

39. By Khalid Mojahid

Made by Khalid Mojahid. Convert a number from decimal to binary using c++. Source

Enter a decimal number: 47
47 in decimal = 101111 in binary 
#include <iostream>
#include<cmath>
using namespace std;

long long convert(int n);

int main() {
  long long n; 
   cout<<"Enter a decimal number: "<<endl;
   cin>>n;
   cout<<n<<" in decimal = "<<convert(n)<<" in binary "; 
   return 0; } 
   
long long convert(int n) { 
    long long bin = 0;
    int rem, i = 1;
     while (n != 0) {
      rem = n % 2;
      n /= 2;
      bin += rem * i;
      i *= 10; } 
      return bin; }

40. By Med Arezki

Made by Med Arezki. Decimal To Binary (For just numbers from 0 to 15 (four digits). Source

Enter your number :10
Your number in bits :1010
#include <iostream>

using namespace std;


int main()
{
    int a(0),b,c,d,e;
    cout<<"Enter your number :";cin>>a;

    cout<<"Your number in bits :";
     b=a/2;
     c=b/2;
     d=c/2;
     e=d/2;

     cout<<d%2<<c%2<<b%2<<a%2;


    return 0;
}

41. By Rameshwor Nepal

Made by Rameshwor Nepal. Source

Enter a decimal number: 48
Your binary number: 1 1 0 0 0 0 
#include <iostream>
#include <stdlib.h>


using namespace std;
int a1, a2, remainder;
int tab = 0;
int maxtab = 0;
int table[0];
int main()
{
    system("clear");
    cout << "Enter a decimal number: ";
    cin >> a1;
    a2 = a1; //we need our number for later on so we save it in another variable

    while (a1!=0) //dividing by two until we hit 0
    {
        remainder = a1%2; //getting a remainder - decimal number(1 or 0)
        a1 = a1/2; //dividing our number by two
        maxtab++; //+1 to max elements of the table
    }

    maxtab--; //-1 to max elements of the table (when dividing finishes it adds 1 additional elemnt that we don't want and it's equal to 0)
    a1 = a2; //we must do calculations one more time so we're gatting back our original number
    table[0] = table[maxtab]; //we set the number of elements in our table to maxtab (we don't get 10's of 0's)

    while (a1!=0) //same calculations 2nd time but adding every 1 or 0 (remainder) to separate element in table
    {
        remainder = a1%2; //getting a remainder
        a1 = a1/2; //dividing by 2
        table[tab] = remainder; //adding 0 or 1 to an element
        tab++; //tab (element count) increases by 1 so next remainder is saved in another element
    }

    tab--; //same as with maxtab--
    cout << "Your binary number: ";

    while (tab>=0) //until we get to the 0 (1st) element of the table
    {
        cout << table[tab] << " "; //write the value of an element (0 or 1)
        tab--; //decreasing by 1 so we show 0's and 1's FROM THE BACK (correct way)
    }

    cout << endl;
    return 0;
}

42. By Adam Staes

Made by Adam Staes. Source

10
1010
#include <iostream>
#include <list>

using namespace std;

int main()
{
    int n;
    list<bool> bin;
    
    cin >> n;

    do{
        bin.push_front((n % 2));
        n = (n - n % 2) / 2;
    } while (n > 0);

    for (bool x : bin)
    {
        cout << (x?1:0);
    }

    cout << endl;
    
    return 0;
}

43. By harshini

Made by harshini. Source

enter decimal number
11
in binary :1011
#include <iostream>
using namespace std;

int main()
{
     int rem[20];
     int n,i,j;
     cout<<"enter decimal number";
     cin>>n;
     for(i=0;n!=0;i++)
     {
     rem[i]=n%2;
     n=n/2;
     }
     cout<<"\n"<< " in binary :";
     for(j=i-1;j>=0;j--)
     {
         cout<<rem[j];
     }
     

    return 0;
}

44. By Aarti Rani

Made by Aarti Rani. Basic C++ Decimal to Binary program. Source

enter the decimal to change in binary:12
the binary number is:1100
#include <iostream>
using namespace std;
int decimaltobinary(int n)
{
    int x=1;
    int ans=0;
    while(x<=n)
    {
        x*=2;
    }
        x/=2;
    while(x>0)
    {
        int lastdigit=n/x;
        n-=lastdigit*x;
        x/=2;
        ans=ans*10+lastdigit;
    }
    return ans;
}

int main() {
    int n;
    cout<<"enter the decimal to change in binary:";
    cin>>n;
    cout<<n<<endl;
    cout<<"the binary number is:";
    cout<<decimaltobinary(n)<<endl;
    return 0;
}