2015 HUAS Summer Trainning #6~H

#include<stdio.h>
const int N=1000000;
int a[N];
int prim(int x)
{
    int i;
    if(x==2)
    return 1;

    for(i=2;i*i<=x;i++)
    if(x%i==0)
    return 0;

    return 1;
}
int main()
{
    int j=0,i,v,m,n,sum,count,f=1;
    a[j++]=2;
    for(i=3;i<=1000000;i+=2)
    if(prim(i))
    {
        int t=i;
		sum=0;
        while(t)
        {
            sum+=t%10;
            t/=10;
        }
    if(prim(sum))
       {
           a[j++]=i;
       }
    }
    scanf("%d",&v);
    while(v--)
    {
        scanf("%d%d",&m,&n);
        count=0;
        for(i=0;a[i]<=n;i++)
        if (a[i]>=m&&a[i]<=n)
        count++;

        printf("Case #%d: %d\n",f++,count);
    }
    return 0;
}