#include<bits/stdc++.h>
#define endl '\n'
using namespace std;
using ll = long long;

void solve() {
    int n;
    cin >> n;
    assert(1 <= n && n <= 200000);
    vector<pair<int, int>> v(n);
    for(auto &[l, r]: v) {
        cin >> l >> r;
        assert(1 <= l && l <= 1000000000);
        assert(1 <= r && r <= 1000000000);
        // cerr << n << endl;
        if(l > r) swap(l, r);
        assert(l <= r);
    }
    sort(v.begin(), v.end(), [&](auto x, auto y) {
        if(x.second == y.second) return x.first <= y.first;
        return x.second < y.second;
    });
    vector<int> ans;
    int last = -1;
    for(auto &[l, r]: v) {
        if(last < l) last = l;
        else {
            if(last >= r) {
                cout << "nO" << endl;
                return;
            }
            last++;
        }
        // cout << l << " " << r << " = " << last << endl;
        ans.push_back(last);
    }
    cout << "YeS" << endl;
    for(auto &i: ans) cout << i << " ";
    cout << endl;
    return;
}

int main() {
    ios::sync_with_stdio(false); cin.tie(0);
    int tc = 1;
    cin >> tc;
    assert(1 <= tc && tc <= 5000);
    for (int t = 1; t <= tc; t++) {
        // cout << "Case " << t << ": ";
        solve();
    }
    return 0;
}