E

#include <bits/stdc++.h>
typedef long long ll;
#define pb push_back
#define ff first
#define ss second
const int N=2e3+7;
const int mod=1e9+7;
using namespace std;

int32_t main()
{
   ios_base::sync_with_stdio(false);
   cin.tie(0);

   int t;
   cin >> t;
   while(t--)
   {
        int n;
        string s;
        cin >> n >> s;

        vector<long long> pre(n);
        for(int i=0;i<n;i++)
        {
            pre[i]=s[i]-'0';
            if(i)
                pre[i]=pre[i]+pre[i-1];
        }

        string ans="";
        long long remainder=0;
        for(int i=n-1;i>=0;i--)
        {
            long long curr=remainder+pre[i];
            ans+=(char)(curr%10+'0');
            remainder=curr/10;
        }

        while(remainder)
        {
            ans+=(char)(remainder%10+'0');
            remainder=remainder/10;
        }

        while(ans.back()=='0')
            ans.pop_back();
        reverse(ans.begin(),ans.end());

        cout << ans << "\n";
   }
}