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

bool isPrime(int num) {
    if (num <= 1) return false;
    for (int i = 2; i * i <= num; i++) {
        if (num % i == 0) return false;
    }
    return true;
}

int main() {
    int n, count = 0, i = 2;
    cin >> n;
    while (true) {
        if (isPrime(i)) {
            count++;
            if (count == n) {
                cout << i;
                break;
            }
        }
        i++;
    }
    return 0;
}