#include <bits/stdc++.h>
using namespace std;
 
int main(){
 ios::sync_with_stdio(0);cin.tie(0);cout.tie(0);
 int t;cin>>t;
 while(t--){
  int n;cin>>n;
  string s;cin>>s;
  vector<int> dig(n,0);
 
  dig[0]=s[0]-'0';
  for(int i=1;i<n;i++)
   dig[i]=dig[i-1]+s[i]-'0';
 
  string ans="";
  for(int i=n-1;i>0;i--){
   ans=(char)((dig[i]%10)+'0')+ans;
   dig[i-1]+=dig[i]/10;
  }
  while(dig[0]){
  	ans=(char)((dig[0]%10)+'0')+ans;
  	dig[0]/=10;
  }
  cout<<ans<<'\n';
  }
  return 0;
}

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

NQoyCjQyCjUKMTIzNDUKMgo5OQo0CjAwMDUKMjcKNDU2NDgwNjk3MjU5NjcxMzA5MDEyNjMxMDAy

5
2
42
5
12345
2
99
4
0005
27
456480697259671309012631002