#include <bits/stdc++.h>
using namespace std;
const int maxn = 110;
struct node {
  int x;
  int y;
};
node a[maxn];
int main() {
  int n;
  scanf("%d", &n);
  for (int i = 0; i < n; i++) {
    int x;
    int d;
    scanf("%d %d", &x, &d);
    a[i].x = x;
    a[i].y = x + d;
  }
  int flag = 0;
  for (int i = 0; i < n - 1; i++) {
    for (int j = i + 1; j < n; j++) {
      if (a[i].x == a[j].y && a[i].y == a[j].x) {
        flag = 1;
        break;
      }
    }
  }
  if (flag)
    printf("YES\n");
  else
    printf("NO\n");
  return 0;
}
