Codeforces Round #793 (Div. 2) D(构造)

/*keep on going and never give up*/
#include<bits/stdc++.h>
using namespace std;
#define int long long
#define ll long long
#define db(x) cerr<<(#x)<<" "<<(x)<<" "<<endl;
#define endl "\n"
#define fast std::ios::sync_with_stdio(false);cin.tie(0);cout.tie(0);
const double E = exp(1);
const double PI = acos(-1.0);
const int mod=1e9+7; 
const int maxn=2e5+10;
int n,m,a[maxn]; 
string s;
void slove() {
    cin>>n>>s;
    vector<int>one,vis(n),last;
    vector<pair<int,int>>ans;
    for (int i=0;i<s.size();i++)if(s[i]=='1')one.push_back(i),vis[i]=1;
    if (one.size()== 0||one.size()%2==1) { cout<<"No\n";return;}
    cout<<"Yes\n";// 把1当作叶子节点，但是放在前面； 
    for (int u:one){
        while (!vis[(u+1)%n]){
            ans.push_back({u,(u+1)%n});
            u++;u%=n;// 把相邻的0之间连起来； 
        }
        last.push_back(u);//储存末端的0； 
    }
    for (int i=1;i<last.size();i++)
        ans.push_back({last[0],last[i]});//把末端的0全连在一起 
    for (auto p:ans)cout<<p.first+1<<" "<<p.second+1<<endl;
}
signed main(){
	fast 
	int t=1;
	cin>>t;
	while(t--){
		slove();
	}
}