#include <bits/stdc++.h>
int main(void) {
  int n;
  scanf("%d", &n);
  int x[20001];
  int d[20001];
  int m[20001];
  for (size_t i = 0; i < n; i++) {
    scanf("%d %d", &x[i], &d[i]);
    m[i] = x[i] + d[i];
  }
  int count = 0;
  for (size_t i = 0; i < n; i++) {
    for (size_t j = i + 1; j < n; j++) {
      if (m[i] == x[j] && m[j] == x[i]) count += 2;
    }
  }
  if (count % 2 == 0 && count >= 2)
    printf("YES");
  else
    printf("NO");
  return 0;
}
