How Program works?

Lets take an example of 11.

Now divide it by 2 and note down the remainder.

So. 11 / 2 , Remainder = 1.

Quotient: 5 / 2 , Remainder = 1.

Quotient: 2/2 , Remainder = 0.

Quotient: 1/2, Remainder = 1.

Now Quotient = 0. Stop.

Binary number is the Remainders in reverse order i.e. Binary of 11 = 1011

PROGRAM:

#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;
}

 

OUTPUT: