Being Code Expert: Three Divisors

Given an integer n, return true if n has exactly three positive divisors. Otherwise, return false.

An integer m is a divisor of n if there exists an integer k such that n = k * m.

Example 1:

Input: n = 2
Output: false
Explantion: 2 has only two divisors: 1 and 2.

Example 2:

Input: n = 4
Output: true
Explantion: 4 has three divisors: 1, 2, and 4.

Approach

Java

public class ThreeDivisors {
    public static void main(String[] args) {
        int n = 4;

        System.out.println(isThree(n));

    }

    static boolean isThree(int n) {

        int cnt = 0;
        for (int i = 1; i * i <= n; i++) {

            // if i is the divisor of n
            if (n % i == 0) {

                // if n/i and i are same
                if (n / i == i) {
                    cnt++;
                } else
                    cnt += 2;
            }
        }
        if (cnt == 3)
            return true;
        return false;
    }

}

C++

#include <bits/stdc++.h>
using namespace std;

bool isThree(int n)
{

    int cnt = 0;
    for (int i = 1; i * i <= n; i++)
    {

        //if i is the divisor of n
        if (n % i == 0)
        {

            //if n/i and i are same
            if (n / i == i)
            {
                cnt++;
            }
            else
                cnt += 2;
        }
    }
    if (cnt == 3)
        return true;
    return false;
}
int main()
{
    int n = 4;

    if (isThree(n))
        cout << "true\n";

    else
        cout << "false\n";

    return 0;
}