不要用memset进行二维数组的初始化，会出现严重的错误！！！！！！！！！！！！！！！！！！！！！！！！！

话说，不要用memset进行初始化了8

收获：floyd求解最小环！！！！

get!

#include<iostream>
#include<algorithm>
#include<vector>
#include<cstring>
using namespace std;
#define mem(a,n,val) for(int i=0;i<=n;++i)for(int j=0;j<=n;++j)a[i][j]=val;
typedef long long ll;
const int max_n = 1e5+100;
const int inf = 100000;
ll a[max_n];
int n;
int val[210][210];
int dis[210][210];
inline int floyd() {
  for (int i = 1; i <= n; ++i)
    for (int j = 1; j <= n; ++j) dis[i][j] = val[i][j];
  int ans = inf;
  for (int k = 1; k <= n; ++k) {
    for (int i = 1; i < k; ++i)
      for (int j = 1; j < i; ++j)
        ans = min(ans, dis[i][j] + val[i][k] + val[k][j]);
    for (int i = 1; i <= n; ++i)
      for (int j = 1; j <= n; ++j)
        dis[i][j] = min(dis[i][j], dis[i][k] + dis[k][j]);
  }
  return ans;
}
int main(){
    ios::sync_with_stdio(0);
    cin>>n;int nn = 0;
    for (int i=1;i<=n;++i){
        ll num;cin>>num;
        if (num!=0)a[++nn]=num;
    }n=nn;
    if (n>=210){
        cout<<"3\n";
    }
    else{
        for (int i=0;i<=n;++i){
            for (int j=0;j<=n;++j){
                cout<<val[i][j]<<" ";
            }puts("");
        }
        for (int i=1;i<=n;++i){
            for (int j=i+1;j<=n;++j){
                if (a[i]&a[j]){
                    val[i][j]=1;
                    val[j][i]=1;
                }
            }
        }
        int ans = floyd();
        if (ans==inf)cout<<"-1\n";
        else cout<<ans<<endl;
    }
}