#include <bits/stdc++.h>
using namespace std;
const double pi = 2.0 * acos(0.0);
const double eps = 1.0e-9;
const int dr[] = {-1, 0, 1, 0}, dc[] = {0, 1, 0, -1};
const int dr6[] = {1, 1, 0, -1, -1, 0}, dc6[] = {0, 1, 1, 0, -1, -1};
const int dr8[] = {-1, -1, 0, 1, 1, 1, 0, -1},
          dc8[] = {0, 1, 1, 1, 0, -1, -1, -1};
int main(void) {
  istream& is = cin;
  ostream& os = cout;
  int kase = 1000000000;
  for (int ks = 1, n, x[128], d[128]; ks <= kase && is >> n; ++ks) {
    for (int i = 0; i < n; ++i) is >> x[i] >> d[i];
    bool yes = false;
    for (int i = 0; i < n; ++i)
      for (int j = i + 1; j < n; ++j)
        if (x[i] + d[i] == x[j] && x[i] == x[j] + d[j]) yes = true;
    os << (yes ? "YES" : "NO") << endl;
  }
  return 0;
}
