LightOJ1370 Bi-shoe and Phi-shoe

#include<cmath>
#include<cstdio>
#include<cstring>
#include<iostream>
#include<algorithm>
using namespace std;
const int maxn = 1e6+10;
int book[maxn];
void Init()
{
    memset(book,1,sizeof(book));
    for(int i = 2; i < maxn; i++)
    {
        if(book[i])
        for(int j = 2*i; j < maxn; j += i)
            book[j] = 0;
    }
}
int main(void)
{
    Init();
    int t;
    scanf("%d",&t);
    for(int kase = 1; kase <= t; kase++)
    {
        long long sum = 0;
        int n;
        scanf("%d",&n);
        while(n--)
        {
            int m;
            scanf("%d",&m);
            for(int i = m+1; ;i++)
            {
                if(book[i])
                {
                    sum += i;
                    break;
                }
            }
        }
        printf("Case %d: %lld Xukha\n", kase, sum);
    }
    return 0;
}