View Code of Problem 120

#include <iostream>
#include <math.h>
using namespace std;

bool isprime(int n){
  if(n<=1)
    return false;
  int bound = (int)sqrt(n)+1;
  for(int j=2;j<bound;j++){
    if(n%j==0)
      return false;
  }
  return true;
}

int main(){
  int h1,m1,h2,m2,sum,count,h,m,time1,time2;
  while(scanf("%2d:%2d",&h1,&m1)!=EOF){
    scanf("%2d:%2d",&h2,&m2);
    count = 0;
    time1 = h1*60+m1;
    time2 = h2*60+m2;
    for(int j=time1;j<=time2;j++){
      m = j%60;
      h = j/60;
      if(isprime(h*2500+m))
        count++;
    }
    
    printf("%d\n",count);
  }
  return 0;
}