Example: Decimal to Binary Conversion (Recursive) in C++

C
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Java
Python
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// Decimal to Binary Conversion (Recursive)
#include <iostream>

// Recursive function to convert decimal to binary
void decToBinary(int n) {
    if (n == 0) {
        return; // Base case: nothing to do if number is 0
    }
    decToBinary(n / 2); // Recurse with n divided by 2
    std::cout << n % 2; // Print the remainder after the recursive call returns
}

int main() {
    // Step 1: Declare variable
    int decimalNum;

    // Step 2: Prompt user for input
    std::cout << "Enter a positive decimal number: ";
    std::cin >> decimalNum;

    // Step 3: Handle the special case of 0
    if (decimalNum == 0) {
        std::cout << "Binary equivalent: 0" << std::endl;
    } else {
        // Step 4: Call the recursive function
        std::cout << "Binary equivalent: ";
        decToBinary(decimalNum);
        std::cout << std::endl;
    }

    return 0;
}