Submission

Score: 75

User: wleo.lwo

Problemset: จำนวนเฉพาะก่อนหน้า

Language: cpp

Time: 0.012 second

Submitted On: 2025-10-12 13:21:12

#include <stdio.h>

int main() {
    int n;
    scanf("%d",&n);
    int arr[n+1];
    
    for(int i=0;i<=n;i++){
    	arr[i]=0;
	}
	
	for(int i=2;i<=n;i++){
		if(arr[i]==0){
			int x=i;
			for(int j=x+x;j<=n;j+=x){
				arr[j]=1;
			}
		}
	}
	
	int c=0,a=4,prime[5];
	
	for(int i=n;i>0;i--){
		if(c<5)
			if (arr[i]==0){
				prime[a]=i;
				a--;
				c++;
			}
	}
	
	for(int i=0;i<5;i++){
		printf("%d ",prime[i]);
	}
    
    
    return 0;
}