#include <iostream> #include <queue> #include <map> #include <set> #include <cmath> #include <cstring> #include <algorithm> #include <iomanip> #include <stack> #include <numeric> #include <ctime> #include <string> #include <bitset> #include <unordered_map> #include <unordered_set> #include <bits/stdc++.h> #define il inline using namespace std; using ll = long long; using ull = unsigned long long; const ll N = 1e4 + 5, mod = 1e9 + 7, inf = 2e18; il void solve() { int q; cin >> q; map<ll, ll>mp; while (q--) { ll op, add; cin >> op >> add; mp[op] += add; } for (auto [x, y] : mp) { cout << x << " " << y << '\n'; } } int main() { ios::sync_with_stdio(0), cin.tie(0), cout.tie(0); int t = 1; //cin >> t; while (t--) { solve(); } return 0; }