#include <bits/stdc++.h>
using namespace std;
int main() {
  int *xi, *di, n;
  cin >> n;
  xi = new int[n];
  di = new int[n];
  for (int i = 0; i < n; i++) cin >> xi[i] >> di[i];
  for (int i = 0; i < n; i++) {
    for (int j = 0; j < n; j++) {
      if (xi[i] + di[i] == xi[j] && xi[j] + di[j] == xi[i] && j != i) {
        cout << "YES";
        return 0;
      }
    }
  }
  cout << "NO";
  return 0;
}
