#include<bits/stdc++.h>

using namespace std;

#define int long long
#define double long double

#define pii pair<int,int>
#define vii vector<pii>

#define fi first
#define se second

#define pb push_back
const double eps=1e-12;
const int MAX = 1e16;

signed main(){
    cin.tie(NULL);
    ios_base::sync_with_stdio(false);
    int t;
    cin >> t;
    while(t--) {
        int n;
        cin >> n;
        map<int,int> occupied;
        for(int i = 0; i < n; ++i) {
            int c, d;
            cin >> c >> d;
            int val = MAX - c - d;
            while(occupied[val] == 1) {
                occupied[val] = 0;
                ++val;
            }
            occupied[val]++;
        }
        int maxim = 0;
        int second_maxim = 0;
        for(auto& x : occupied) {
            if(x.second == 0) continue;
            if(x.first >= maxim) {
                second_maxim = maxim;
                maxim = x.first;
            }
            else if(x.first > second_maxim)
                second_maxim = x.first;
        }
        bool can = true;
        if(maxim > MAX + 1) {
            can = false;
        }
        else if(maxim == MAX + 1) {
            if(second_maxim >= MAX) {
                can = false;
            }
        }
        cout << (can? "YES" : "NO") << '\n';
    }

}