#include <bits/stdc++.h>

#define all(a) a.begin(),a.end()
#define len(a) (int)(a.size())
#define fir first
#define sec second
#define fi first
#define se second
#define mp make_pair
#define pb push_back

using namespace std;

typedef pair<int, int> pii;
typedef long long ll;
typedef long double ld;

template<typename T>
bool umin(T &a, T b) {
    if (b < a) {
        a = b;
        return 1;
    }
    return 0;
}

template<typename T>
bool umax(T &a, T b) {
    if (a < b) {
        a = b;
        return 1;
    }
    return 0;
}

#ifdef KIVI
#define DEBUG for (int _____DEBUG=1;_____DEBUG;_____DEBUG=0)
#define LOG(...) prnt(#__VA_ARGS__" ::",__VA_ARGS__)<<endl

template<class ...Ts>
auto &prnt(Ts ...ts) { return ((cerr << ts << " "), ...); }

#else
#define DEBUG while (false)
#define LOG(...)
#endif

const int max_n = -1, inf = 1000111222;

void solve() {
    int n;
    cin >> n;
    vector<pii> v(n);
    for (int i = 0; i < n; i++) {
        cin >> v[i].fir >> v[i].sec;
    }
    int mx = 0;
    for (int i = 0; i < n; i++) {
        mx = max(mx, v[i].fir + v[i].sec);
    }
    set<int> left;
    set<int> right;
    auto add = [&](set<int> &s, int val) {
        while (s.count(val)) {
            s.erase(val);
            val++;
        }
        s.insert(val);
    };
    auto cmp = [&](set<int> a, set<int> b)
    {
        if (a==b){
            return 0;
        }
        vector<int> aa(all(a));
        vector<int> bb(all(b));
        reverse(all(aa));
        reverse(all(bb));
        return aa<bb ? -1 : +1;
    };
    add(right,mx);
    add(right,mx);
    add(right,mx);
    for (int i=0;i<n;i++){
        add(left,mx-(v[i].fir+v[i].sec));
    }
    int res=cmp(left,right);
    if (res==-1){
        cout<<"YES"<<"\n";
    }
    else{
        cout<<"NO"<<"\n";
    }
}

int main() {
//    freopen("input.txt","r",stdin);
//    freopen("output.txt","w",stdout);
    ios_base::sync_with_stdio(0);
    cin.tie(0);

//    ld res=0;
//    for (int i=0;i<30;i++){
//        for (int j=0;j<30;j++){
//            res+=ld(1)/ld((1ll<<(i+j)));
//        }
//    }
//    LOG(res);

    int tests;
    cin>>tests;
    while (tests--){
        solve();
    }

    exit(0);
}