#include <bits/stdc++.h>
using namespace std;

vector<int> A, B;
int main() {
    int T; scanf("%d", &T);
    while (T--) {
        int n; scanf("%d", &n);
        B.clear(), A.clear();
        for (int i = 1; i <= n; i++) {
            int x, y; scanf("%d%d", &x, &y);
            if (x == 1) A.push_back(y);
            else B.push_back(y);
        }
        sort(A.begin(), A.end()),sort(B.begin(), B.end());
        if (!A.size()) cout << B[B.size() - 1] + 2 << endl;
        else if (!B.size()) cout << A[A.size() - 1] + 1 << endl;
        else {
            int x = A[A.size() - 1], y = B[B.size() - 1];
            if (y >= x) printf("%d\n", y + 2);
            else {
                if (y + 1 == x) printf("%d\n", x + 2);
                else printf("%d\n", x);
            }
        }
    }
}