View Code of Problem 120

#include <stdio.h>
#include <stdlib.h>
#include <math.h>
int IsPrime(int n)
{
    int i;
    for(i=2;i<=sqrt(n);i++)
    {
        if(n%i==0)
        {
            return 0;
        }
    }
    return 1;
}

int main()
{
    int h1,m1,h2,m2,sum1,sum2,i,count,j;
    while(scanf("%d:%d",&h1,&m1)!=EOF)
    {
    scanf("%d:%d",&h2,&m2);
    sum1=sum2=count=0;
    sum1=h1*60+m1;
    sum2=h2*62+m2;
    for(i=sum1;i<=sum2;i++)
    {
        j=(i/60)*2500+(i%60);
        if(IsPrime(j))
        {
            count++;
        }
    }
    printf("%d\n",count);
    }
    return 0;
}