#include <bits/stdc++.h>
#define For(i,a,b) for(int i=a;i<=b;i++)
#define Rev(i,a,b) for(int i=a;i>=b;i--)
#define Fin(file) freopen(file,"r",stdin)
#define Fout(file) freopen(file,"w",stdout)
using namespace std;
const int N=0; typedef long long ll;
const int A[6]={1,3,2,6,4,5};
int calc(int x,int c){
    int res=0; For(i,0,c%6-1) res+=A[i];
    return res*x%7;
}
void print(vector< pair<int,int> > ans){
    cout<<ans.size()<<'\n';
    for(auto pr:ans) cout<<pr.second<<' '<<pr.first<<'\n';
}
int cy;
void solve(int T){
    vector<int> a(10); For(i,0,9) cin>>a[i];
    // if(T==1&&a[0]==2) cy=1;
    // if(cy){
    //     if(T==121) { For(i,0,9) cout<<a[i]<<' ';  cout<<endl; }
    //     return;
    // }
    vector<int> cnt(7); For(i,0,9) cnt[i%7]+=a[i];
    vector<int> lis; For(i,0,6) if(cnt[i]) lis.push_back(i);
    vector<int> tmp(7); vector< pair<int,int> > ans;
    if(lis.size()>=4u){
        For(i,0,3) tmp[lis[i]]=1;
    }
    else if(lis.size()==3u){
        int c2=0; For(i,0,2) if(cnt[lis[i]]>=2) c2++;
        if(c2>=2){
            c2=2; For(i,0,2) if(c2&&cnt[lis[i]]>=2) { c2--; tmp[lis[i]]=2; } else tmp[lis[i]]=1;
        }
        else{
            int c4=-1; For(i,0,2) if(cnt[lis[i]]>=4) { c4=i; break; }
            if(c4!=-1){
                For(i,0,2) if(i==c4) tmp[lis[i]]=4; else tmp[lis[i]]=1;
            }
            else{
                tmp=cnt;
            }
        }
    }
    else if(lis.size()==2u){
        if(cnt[lis[0]]>=3&&cnt[lis[1]]>=2){
            tmp[lis[0]]=3; tmp[lis[1]]=2;
        }
        else if(cnt[lis[0]]>=2&&cnt[lis[1]]>=3){
            tmp[lis[0]]=2; tmp[lis[1]]=3;
        }
        else{
            tmp=cnt;
        }
    }
    else{
        int u=lis[0];
        if(calc(u,cnt[u])==0){
            For(i,0,9) if(i%7==u) ans.emplace_back(i,a[i]);
            print(ans);
        }
        else{
            cout<<"-1\n";
        }
        return;
    }
    int cur=0; vector<int> cp;
    For(i,0,9){
        if(a[i]>=tmp[i%7]) { ans.emplace_back(i,a[i]-tmp[i%7]); cur=(cur*A[(a[i]-tmp[i%7])%7]+calc(i,a[i]-tmp[i%7]))%7; while(tmp[i%7]--){cp.push_back(i);} tmp[i%7]=0; }
        else For(_,1,a[i]) { tmp[i%7]--; cp.push_back(i); }
    }
    int sz=cp.size(),ok=0;
    do{
        int res=cur*A[sz%6]%7;
        For(i,0,sz-1) res=(res+cp[i]*A[i%7])%7;
        if(res==0){
            ok=1; Rev(i,sz-1,0) ans.emplace_back(cp[i],1);
            break;
        }
    }while(next_permutation(cp.begin(),cp.end()));
    if(ok) print(ans);
    else cout<<"-1\n";
}
signed main(){
    ios::sync_with_stdio(false); cin.tie(0); cout.tie(0);
    int T,Ti=0; cin>>T; while(T--) solve(++Ti);
    cerr<<"Time = "<<clock()<<" ms"<<endl;
    return 0;
}

// START TYPING IF YOU DON'T KNOW WHAT TO DO