1 #include<iostream>
 2 #include<stdio.h>
 3 #include<string.h>
 4 #include<algorithm>
 5 using namespace std;
 6 int a[100050];
 7 int s[1005];
 8 bool su(int x){
 9     if(x%2==0) return false;
10     else {
11         for(int i=3;i*i<=x;i=i+2){
12             if(x%i==0) return false;
13         }
14         return true;
15     }
16 }
17 int main()
18 {
19     int T;
20     s[0]=2;
21     int t=1;
22     for(int i=3;t<1003;i++)
23         if(su(i)){
24             s[t]=i;
25             t++;
26         }
27     cin>>T;
28     while(T--)
29     {
30         int n;
31         scanf("%d",&n);
32         memset(a,0,sizeof(a));
33         for(int i=0;i<n;i++)
34             scanf("%d",&a[i]);
35         bool flag=false;
36         for(int i=0;i<t;i++)
37         {
38             int sum=0;
39             for(int j=0;j<n;j++){
40                 if(a[j]%s[i]==0){
41                     sum++;
42                 }
43             }
44             if(sum==n){
45                 flag=true;
46                 break;
47             }
48         }
49         if(flag) cout<<"Yes"<<endl;
50         else cout<<"No"<<endl;
51     }
52     return 0;
53 }

 1 #include <iostream>
 2 #include <cstring>
 3 #include <string>
 4 #include <queue>
 5 #include <vector>
 6 #include <map>
 7 #include <set>
 8 #include <stack>
 9 #include <cmath>
10 #include <cstdio>
11 #include <algorithm>
12 #define N 100010
13 #define M 1000000
14 #define LL __int64
15 #define inf 0x3f3f3f3f
16 #define lson l,mid,ans<<1
17 #define rson mid+1,r,ans<<1|1
18 using namespace std;
19 const LL mod = 1e9 + 7;
20 const double eps = 1e-9;
21 LL num[N];
22 LL gcd(LL a, LL b) {
23     return b == 0 ? a : gcd(b, a%b);
24 }
25 int main() {
26     cin.sync_with_stdio(false);
27     int n, T;
28     cin >> T;
29     while (T--) {
30         cin >> n;
31         for (int i = 0; i < n; i++) {
32             cin >> num[i];
33         }
34         if (n == 1) {
35             if (num[0] >= 2) {
36                 cout << "Yes" << endl;
37             }
38             else {
39                 cout << "No" << endl;
40             }
41         }
42         else {
43             LL ans = gcd(num[0], num[1]);
44             for (int i = 2; i < n; i++) {
45                 ans = gcd(ans, num[i]);
46             }
47             if (ans >= 2) {
48                 cout << "Yes" << endl;
49             }
50             else {
51                 cout << "No" << endl;
52             }
53         }
54     }
55     return 0;
56 }