C++ 代码

#include <iostream>
#include <cstring>
#include <cmath>
#include <algorithm>
using namespace std;

const int N = 1e4 + 1;
int ans[N];

bool is_prime(int x)
{
    for (int i = 2; i <= sqrt(x); i++)
    {
        if (x % i == 0) return 0;
    }

    return 1;
}

int main()
{
    ans[1] = 2;
    int idx = 2, k;

    for (int i = 3; ; i++)
    {
        if (is_prime(i)) ans[idx++] = i;
        if (idx > 10000) break;
    }

    while (cin >> k)
        printf("%d\n", ans[k]);

    return 0;

}