Reseto

Author: Pakin Olanraktham

---

View Problem Statement

Source: PROGRAMMING.IN.TH

Difficulty: ?

Prerequisites:

• การเขียนโปรแกรมเบื้องต้น

View External Solution

เฉลย

CC++

#include <stdio.h>

int main() {
    int n, k;
    scanf("%d %d", &n, &k);
    int alr[n+1]={};

    int c = 0, j = 2;
    while (1) {
        if (!alr[j]) {
            for (int i = j; i <= n; i += j) {
                if (!alr[i]) {
                    c++;
                    alr[i] = 1;
                    if (c == k) {
                        printf("%d", i);
                        return 0;
                    }
                }
            }
        }
        j++;
    }
}

#include <iostream>
#include <vector>

using namespace std;

int main() {
    int n, k;
    cin >> n >> k;
    vector<int> alr(n+1);

    int c = 0, j = 2;
    while (1) {
        if (!alr[j]) {
            for (int i = j; i <= n; i += j) {
                if (!alr[i]) {
                    c++;
                    alr[i] = 1;
                    if (c == k) {
                        cout << i;
                        return 0;
                    }
                }
            }
        }
        j++;
    }
    return 0;
}