C++ Exercises: Compute square root of a given non-negative integer

Last update on December 20 2024 12:24:06 (UTC/GMT +8 hours)

Write a C++ program to compute the square root of a given non-negative integer. Return type should be an integer.

Sample Input: n = 81
Sample Output: Square root of 81 = 9
Sample Input: n = 8
Sample Output: Square root of 8 = 2

Sample Solution:

C++ Code :

#include <iostream>

using namespace std;

// Function to find the square root of a number using binary search
int square_root(int num1) {
    long left_part = 0; // Initializing the left boundary
    long right_part = num1 / 2 + 1; // Initializing the right boundary

    // Implementing binary search to find the square root
    while (left_part <= right_part) {
        long mid = left_part + (right_part - left_part) / 2; // Calculating the midpoint
        long result = mid * mid; // Calculating the square of the midpoint

        // Checking conditions to adjust the boundaries and find the square root
        if (result == (long)num1) {
            return (int)mid; // If square of mid equals the number, return mid as square root
        } else if (result > num1) {
            right_part = mid - 1; // If square of mid is greater, adjust the right boundary
        } else {
            left_part = mid + 1; // If square of mid is smaller, adjust the left boundary
        }
    }
    return (int)right_part; // Returning right_part as square root
}

// Main function to test the square_root function
int main() {
    int n = 81;
    cout << "\nSquare root of " << n << " = " << square_root(n) << endl; // Testing square root of 81
    n = 8;
    cout << "\nSquare root of " << n << " = " << square_root(n) << endl; // Testing square root of 8
    n = 627;
    cout << "\nSquare root of " << n << " = " << square_root(n) << endl; // Testing square root of 627
    n = 225;
    cout << "\nSquare root of " << n << " = " << square_root(n) << endl; // Testing square root of 225
    return 0;
}

Sample Output:

Square root of 81 = 9

Square root of 8 = 2

Square root of 627 = 25

Square root of 225 = 15

Flowchart:

C++ Code Editor:

Click to Open Editor

Contribute your code and comments through Disqus.

Previous: Write a C++ program to compute the sum of two given binary strings.
Next: Write a C++ program to count the prime numbers less than a given positive number.