C++ Exercises: Find one's complement of a binary number

C++ For Loop: Exercise-64 with Solution

Write a program in C++ to find the one's complement of a binary number.

Sample Solution:-

C++ Code :

#include <iostream> // Including the input/output stream library
#define SZ 8 // Defining a constant named SZ with a value of 8

using namespace std; // Using the standard namespace

int main() // Main function where the execution of the program starts
{
    int i; // Declare an integer variable 'i'
    char binary[SZ + 1], onesComp[SZ + 1]; // Declare character arrays to store binary values and their one's complement
    int error = 0; // Initialize an error flag

    // Display messages asking for input
    cout << "\n\n Find one's complement of a binary value:\n";
    cout << "----------------------------------------------\n";
    cout << " Input a " << SZ << " bit binary value: ";
    cin >> binary; // Read a binary value from the user

    // Loop to find the one's complement of the entered binary value
    for (i = 0; i < SZ; i++) 
    {
        if (binary[i] == '1') // Check if the current bit is '1'
        {
            onesComp[i] = '0'; // If '1', replace it with '0' in the one's complement
        }
        else if (binary[i] == '0') // Check if the current bit is '0'
        {
            onesComp[i] = '1'; // If '0', replace it with '1' in the one's complement
        }
        else // If the input value contains any other character than '0' or '1'
        {
            cout << "Invalid Input. Input the value of assign bits." << endl; // Display an error message
            error = 1; // Set error flag to 1
            break; // Exit the loop
        }
    }

    onesComp[SZ] = '\0'; // Assign null terminator at the end of the one's complement array

    if (error == 0) // If no error occurred during input processing
    {
        // Display the original binary value and its one's complement
        cout << " The original binary = " << binary << endl;
        cout << " After ones complement the number = " << onesComp << endl;
    }
}

Sample Output:

 Find one's complement of a binary value:                              
----------------------------------------------                         
 Input a 8 bit binary value: 10100101                                  
 The original binary = 10100101                                        
 After ones complement the number = 01011010

Flowchart:

C++ Code Editor:

Contribute your code and comments through Disqus.

Previous: Write a program in C++ to enter any number and print all factors of the number.
Next: Write a program in C++ to find two's complement of a binary number.