#include<bits/stdc++.h>
#define N 100005
#define ll long long
using namespace std;
int T;
int n;
int x,y;
int ans;
int pos1[N],p1;
int pos2[N],p2;
void solve() {
    ans = 0;
    p1 = 0;
    p2 = 0;
    scanf("%d",&n);
    for(int i=0; i<n; i++) {
        scanf("%d",&x);
        if(x == 1) {
            scanf("%d",&pos1[p1++]);
        } else {
            scanf("%d",&pos2[p2++]);
        }
    }
    sort(pos1,pos1+p1);
    sort(pos2,pos2+p2);
    if(p1) {
        ans = pos1[p1-1] + 1;
        if(p2) {
            if(pos2[p2-1] >= pos1[p1-1]) {
                ans = pos2[p2-1] + 2;
            } else {
                ans = max(ans,pos2[p2-1]+3);
            }
        }
    } else {
        ans = pos2[p2-1]+2;
    }
    
    printf("%d\n",ans);
}

int main() {
    scanf("%d",&T);
    while(T--) {
        solve();
    }
    return 0;
}