Submission

Score: 0

User: colo39

Problemset: จำนวนเฉพาะก่อนหน้า

Language: cpp

Time: 0.003 second

Submitted On: 2026-09-30 16:31:59

#include <bits/stdc++.h>
using namespace std;
int a[10000005];

vector<int> arr;
int main () {
    ios_base::sync_with_stdio(false);
    cin.tie(0);
    int n;
    cin >> n;
    for (int i = 2;i <= n;i++) {
        for (int j = i;j <= n;j+=i) {
            if (j==i) continue;
            a[j] = 1;
        }
    }
    for (int i = 2;i <= n;i++) {
        if (!a[i]) arr.push_back(i);
    }



    
    int i = lower_bound(arr.begin(),arr.end(),n) - arr.begin();
    if (i-5 >=0)  {
        for (int k = i-5;k <= i-1;k++) {
            cout << arr[k] << " ";
        }
    }   else {
        for (int k = 0;k <= i-1;k++) {
            cout << arr[k] << " ";
        }
    }
    
}