#include<bits/stdc++.h> using namespace std; #define int long long signed main() { int n; cin>>n; while(n--) { int len,cnt=0,flag=0; string s; cin>>len>>s; s+='0'; for(auto& x:s) { if(x=='1') { cnt++; } else { if(cnt==1) { cout<<"NO"<<endl; flag=1; }...