HOJ 1015 Nearly prime numbers

//Nearly prime number is an integer positive number for which it is possible 
//to find such primes P1 and P2 that given number is equal to P1*P2.
#include <stdio.h>
#include <stdlib.h>
#include <math.h>

//decide n whither is a nearly prime number or not,
//is then return true,or return false.
bool isNPN(int n);
//decide n whither is a prime number or not,
//is then return true,or return false.
bool isPrime(int n);

int main()
{
    int input[50000];    
    int num;
    
    //input
    scanf("%d", &num);
    for (int i=0; i<num; i++)
    {
        scanf("%d", &input[i]);
    }

    //start resolve the problem here
    for (int i=0; i<num; i++)
    {
        if (isNPN(input[i]))
        {
            printf("Yes\n");
        }
        else
        {
            printf("No\n");
        }
    }

    return 0;
}

bool isNPN(int n)
{
    int m = (int)sqrt((double)n) + 1;

    if (n%2==0 && isPrime(n/2))
    {
        return true;
    }
    for (int i=3; i<m; i+=2)
    {
        if (n%i == 0 && isPrime(i))
        {
            if (isPrime(n/i))
            {
                return true;
            }
        }
    }
    return false;
}

bool isPrime(int n)
{
    int m = (int)sqrt((double)n) + 1;
    
    if (n == 2)
    {
        return true;
    }
    if (n%2 == 0)
    {
        return false;
    }
    for(int i=3; i<m; i+=2)
    {
        if (n%i==0)
        {
            return false;
        }
    }
    return true;
}