Program for Decimal to Binary Conversion in C++

Decimal to Binary Conversion

Converting a decimal number to binary involves representing the number in base-2, where each digit is either 0 or 1.

We will explore three methods to perform this conversion using C++ programming.

Method 1: Using Bitwise Operators

We use bitwise operations to extract each bit from the number.

#include <iostream>
using namespace std;

void decimalToBinary_bitwise(int n) {
    for (int i = 31; i >= 0; i--) {
        cout << ((n >> i) & 1);
    }
    cout << endl;
}

int main() {
    int num;
    cout << "Enter a decimal number: ";
    cin >> num;
    decimalToBinary_bitwise(num);
    return 0;
}
            

Method 2: Using Division by 2

We repeatedly divide the number by 2 and store the remainder.

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

void decimalToBinary_division(int n) {
    vector binary;
    while (n > 0) {
        binary.push_back(n % 2);
        n /= 2;
    }
    for (auto it = binary.rbegin(); it != binary.rend(); ++it) {
        cout << *it;
    }
    cout << endl;
}

int main() {
    int num;
    cout << "Enter a decimal number: ";
    cin >> num;
    decimalToBinary_division(num);
    return 0;
}
            

Method 3: Using Recursion

We use recursion to keep dividing the number by 2 until it becomes 0, printing the remainder in reverse order.

#include <iostream>
using namespace std;

void decimalToBinary_recursive(int n) {
    if (n == 0)
        return;
    decimalToBinary_recursive(n / 2);
    cout << (n % 2);
}

int main() {
    int num;
    cout << "Enter a decimal number: ";
    cin >> num;
    if (num == 0)
        cout << "0";
    else
        decimalToBinary_recursive(num);
    cout << endl;
    return 0;
}