#include<bits/stdc++.h>
using namespace std;
const int mod=1e9+7;
void solve(int idx){
    map<int,int> mp;
    int n;
    cin>>n;
    for(int i=1;i<=n;i++){
        int a,x;
        cin>>a>>x;
        mp[a]+=x;
    }
    for(auto it=mp.begin();it!=mp.end();it++){
        int a=it->first;
        int x=it->second;
        mp[a]=0;
        for(int j=0;(1<<j)<=x;j++){
            if(x>=(1<<j)){
                mp[a+j]++;
                x-=(1<<j);
            }
        }
        if(x>0){
            for(int j=0;(1<<j)<=x;j++){
                if((x>>j)&1){
                    mp[a+j]++;
                    x-=(1<<j);
                }
            }
        }
    }
    vector<pair<int,int>> b;
    b.push_back(make_pair(-5,0));
    int cnt=0;
    for(auto v:mp){
        b.push_back(v);
        cnt++;
    }
    //vector<vector<int>> dp(b.size(),vector<int>(2,0));
    int ans=1;
    //dp[0][0]=1;
    int dp0=1;
    int dp1=0;
    for(int i=1;i<=cnt;i++){
        if(b[i-1].first+1!=b[i].first){
            ans=1ll*ans*((dp0+dp1)%mod)%mod;
            dp0=1;
            dp1=0;
        }
        if(b[i].second==2){
            dp1=(dp0+dp1)%mod;
        }
        dp0=dp0*2%mod;
    }
    ans=1ll*ans*((dp0+dp1)%mod)%mod;
    cout<<"Case #"<<idx<<": "<<ans<<'\n';
}
int main(){
    ios::sync_with_stdio(false);
    cin.tie(0);
    cout.tie(0);
    int T;
    cin>>T;
    int idx=1;
    while(T--){
        solve(idx++);
    }
    return 0;
}