//Δ_1004
#include<iostream>
#include<cstdio>
#include<fstream>
#include<algorithm>
#include<vector>
#include<map>
#include<set>
#include<queue>
#include<bitset>
#include<cmath>
#include<cstring>
#include<cstdlib>
using namespace std;
typedef long long LL;
typedef double DB;
const int inf = 1e9;
int a[11];
int main()
{
    int T,n,x,y;
    scanf("%d",&T);
    while(T--){
        scanf("%d",&n);
        a[1]=-inf,a[2]=-inf;
        while(n--){
            scanf("%d%d",&x,&y);
            a[x]=max(a[x],y);
        }
        a[1]+=1,a[2]+=2;
        printf("%d\n",max(a[1],a[2])+(a[1]==a[2]));
    }
    return 0;
}