#include <bits/stdc++.h>
using namespace std;
struct node {
  int x;
  int d;
} a[105];
int main() {
  int num, i, j;
  int flag = 0;
  cin >> num;
  for (i = 0; i < num; i++) {
    cin >> a[i].x >> a[i].d;
  }
  for (i = 0; i < num - 1; i++) {
    for (j = i + 1; j < num; j++) {
      if (a[i].x + a[i].d == a[j].x && a[j].d + a[j].x == a[i].x) {
        flag = 1;
        break;
      }
    }
    if (flag) break;
  }
  if (flag)
    cout << "YES" << endl;
  else
    cout << "NO" << endl;
  return 0;
}
