5. Write a C++ program to convert Decimal to Binary Number and Binary to Decimal Number code example

Example 1: convert decimal to binary in c++

// C++ program to convert a decimal 
// number to binary number 
  
#include <iostream> 
using namespace std; 
  
// function to convert decimal to binary 
void decToBinary(int n) 
{ 
    // array to store binary number 
    int binaryNum[32]; 
  
    // counter for binary array 
    int i = 0; 
    while (n > 0) { 
  
        // storing remainder in binary array 
        binaryNum[i] = n % 2; 
        n = n / 2; 
        i++; 
    } 
  
    // printing binary array in reverse order 
    for (int j = i - 1; j >= 0; j--) 
        cout << binaryNum[j]; 
} 
  
// Driver program to test above function 
int main() 
{ 
    int n = 17; 
    decToBinary(n); 
    return 0; 
}

Example 2: built in function in c++ for binary to decimal

#include <bits/stdc++.h>

using namespace std;

int main(void){
    bitset<8> bits("1000");
    int ab = bits.to_ulong();
    cout << ab << "\n";
    
    return 0;
}