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

void solve() {
    int n;
    cin >> n;
    vector<pair<int,int>> seg(n);
    for (int i = 0; i < n; i++) cin >> seg[i].first >> seg[i].second;
    sort(seg.begin(), seg.end(), [](auto a, auto b){ return a.second < b.second; });
    vector<int> ans;
    int last = -1; 
    for (auto &s : seg){
        int x = max(last + 1, s.first);
        if (x > s.second) { cout << "NO\n"; return; }
        ans.push_back(x);
        last = x;
    }
    cout << "YES\n";
    for (auto x : ans) cout << x << " ";
    cout << "\n";
}

int main() {
    ios::sync_with_stdio(false);
    cin.tie(nullptr);
    
    int t;
    cin >> t;
    while (t--) solve();
}