#include <stdio.h> #include <math.h> int isPrime(int i){ if(i==1){ return 1; }else{ for(int j=2;j<=sqrt(i);j++){ if(i%j==0){ return 0; break; } } return 1; } } int main(){ int h1,m1,h2,m2; while(scanf("%d:%d",&h1,&m1)!=EOF){ scanf("%d:%d",&h2,&m2); int count=0; int sum1=h1*60+m1; int sum2=h2*60+m2; for(int i=sum1;i<=sum2;i++){ int h=i/60; int m=i%60; int sum=h*2500+m; if(isPrime(sum)){ count++; } } printf("%d\n",count); } } |
Double click to view unformatted code.