#include <bits/stdc++.h>
const int N = 100010;
const long long INF = 1ll << 60;
const int inf = 0x3f3f3f3f;
int t;
int n, m, k;
int a[N];
int b[N];
std::vector<int> row[N];
std::vector<int> col[N];
int cur;
int r, c;
long long ans;
int main() {
  scanf("%d%d%d", &n, &m, &k);
  for (int i = 1; i <= k; ++i) {
    scanf("%d%d", &a[i], &b[i]);
    row[a[i]].push_back(b[i]);
    col[b[i]].push_back(a[i]);
  }
  for (int i = 1; i <= n; ++i) {
    row[i].push_back(m + 1);
    row[i].push_back(0);
    std::sort(row[i].begin(), row[i].end());
  }
  for (int j = 1; j <= m; ++j) {
    col[j].push_back(n + 1);
    col[j].push_back(0);
    std::sort(col[j].begin(), col[j].end());
  }
  r = 1;
  c = 1;
  ans = 1ll;
  int r_max = inf;
  int c_max = inf;
  int r_min = 2;
  int c_min = -inf;
  for (int i = 1; i <= 2 * (n + m) + 1; ++i) {
    if (!cur) {
      auto x = std::lower_bound(row[r].begin(), row[r].end(), c);
      int c_nxt = (*x) - 1;
      c_nxt = std::min(c_nxt, c_max);
      assert(c_nxt >= c);
      ans += c_nxt - c;
      if (c == c_nxt && i != 1) {
        break;
      }
      c = c_nxt;
      c_max = c - 1;
    } else if (cur == 1) {
      auto x = std::lower_bound(col[c].begin(), col[c].end(), r);
      int r_nxt = (*x) - 1;
      r_nxt = std::min(r_nxt, r_max);
      assert(r_nxt >= r);
      ans += r_nxt - r;
      if (r == r_nxt && i != 1) {
        break;
      }
      r = r_nxt;
      r_max = r - 1;
    } else if (cur == 2) {
      auto x = std::lower_bound(row[r].begin(), row[r].end(), c);
      --x;
      int c_nxt = (*x) + 1;
      c_nxt = std::max(c_nxt, c_min);
      assert(c_nxt <= c);
      ans += c - c_nxt;
      if (c == c_nxt && i != 1) {
        break;
      }
      c = c_nxt;
      c_min = c + 1;
    } else if (cur == 3) {
      auto x = std::lower_bound(col[c].begin(), col[c].end(), r);
      --x;
      int r_nxt = (*x) + 1;
      r_nxt = std::max(r_nxt, r_min);
      assert(r_nxt <= r);
      ans += r - r_nxt;
      if (r == r_nxt && i != 1) {
        break;
      }
      r = r_nxt;
      r_min = r + 1;
    }
    cur = (cur + 1) % 4;
  }
  if (ans + k != 1ll * n * m) {
    printf("NO\n");
  } else {
    printf("YES\n");
  }
  return 0;
}
