此篇属于比赛题解集合(CF && AcWing Race)链接

cf round 853 A

CODE

#include<iostream>
#include<algorithm>
#include<cstring>
#include<cstdio>
#include<vector>
#include<queue> 

using namespace std;


const int N = 110;
int a[N];

int gcd(int a,int b)
{
    return b ? gcd(b,a % b) : a;
}

bool check(int n)
{

    for(int i = 1;i <= n;i ++)
    cin >> a[i];

    for(int i = 1;i <= n;i ++)
    for(int j = i + 1;j <= n;j ++)
    if(gcd(a[i],a[j]) <= 2) return true;

    return false;
}

int main()
{   

    int t;cin >> t;
    while(t --)
    {
    int n;cin >> n;
     if(check(n)) puts("Yes");
     else puts("No");
    } 


    return 0;
}