C++ Code For Converting Decimal To Binary

4 min read Jul 01, 2024

C++ Code for Converting Decimal to Binary

This article provides a comprehensive guide on converting decimal numbers to binary numbers using C++. We will explore two popular methods:

1. Using the `%` and `/` Operators

This method involves repeatedly dividing the decimal number by 2 and keeping track of the remainders. The remainders, in reverse order, form the binary equivalent.

Code:

#include 

using namespace std;

int main() {
  int decimalNum, binaryNum[32] = {0}; // Array to store binary digits
  int i = 0; 

  cout << "Enter a decimal number: ";
  cin >> decimalNum;

  while (decimalNum > 0) {
    binaryNum[i] = decimalNum % 2; // Get remainder
    decimalNum /= 2; // Divide by 2
    i++;
  }

  cout << "Binary equivalent: ";
  // Print the binary digits in reverse order
  for (int j = i - 1; j >= 0; j--) {
    cout << binaryNum[j];
  }
  cout << endl;

  return 0;
}

Explanation:

The while loop iterates until the decimal number becomes 0.
In each iteration, we calculate the remainder (decimalNum % 2) and store it in the binaryNum array.
We then divide the decimal number by 2 (decimalNum /= 2) for the next iteration.
The for loop prints the binary digits in reverse order, starting from the last calculated remainder.

2. Using Bitwise Operators

Another efficient way is to use the bitwise & operator and repeatedly shift the decimal number to the right.

Code:

#include 

using namespace std;

int main() {
  int decimalNum;
  
  cout << "Enter a decimal number: ";
  cin >> decimalNum;

  cout << "Binary equivalent: ";
  // Iterate through all bits
  for (int i = 31; i >= 0; i--) {
    // Check if the ith bit is set
    if ((decimalNum >> i) & 1) {
      cout << "1";
    } else {
      cout << "0";
    }
  }
  cout << endl;

  return 0;
}

Explanation:

The for loop iterates through 32 bits (for a 32-bit integer).
We use (decimalNum >> i) & 1 to check if the ith bit is set. If it is set, we print "1"; otherwise, we print "0".
The >> operator shifts the decimal number i positions to the right, isolating the ith bit.
The & 1 operation checks if the isolated bit is 1.

Conclusion

Both methods effectively convert decimal to binary. The % and / approach is more intuitive for beginners, while the bitwise operator method offers a concise and efficient solution. Choose the method that best suits your understanding and requirements.

C++ Code For Converting Decimal To Binary