#include<bits/stdc++.h>
#define endl '\n'
using namespace std;
using ll = long long;
void solve() {
int n;
cin >> n;
vector<pair<int, int>> v(n);
for(auto &[l, r]: v) cin >> 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) {
// cout << l << " " << r << endl;
if(last < l) last = l;
else {
if(last >= r) {
cout << "nO" << endl;
return;
}
last++;
}
ans.push_back(last);
}
cout << "YeS" << endl;
sort(ans.begin(), ans.end());
for(auto &i: ans) cout << i << " ";
cout << endl;
return;
}
int main() {
ios::sync_with_stdio(false); cin.tie(0);
int tc = 1;
cin >> tc;
for (int t = 1; t <= tc; t++) {
// cout << "Case " << t << ": ";
solve();
}
return 0;
}