#include <bits/stdc++.h>

using namespace std;

using pii = pair<int, int>;
pii dp[5010][5010];
int min_x[5010], max_x[5010], min_y[5010], max_y[5010];

pii range_intersect(pii p1, pii p2) {
  if (p1.first < 0 || p2.first < 0) {
    return pii(-1, -1);
  }
  int u = max(p1.first, p2.first);
  int v = min(p1.second, p2.second);
  if (u > v) {
    return pii(-1, -1);
  }
  return pii(u, v);
}

pii range_union(pii p1, pii p2) {
  if (p1.first < 0) {
    return p2;
  }
  if (p2.first < 0) {
    return p1;
  }
  if (p1 >= p2) {
    swap(p1, p2);
  }
  assert(p2.first <= p1.second + 1);
  return pii(p1.first, p2.second);
}

bool inrange(int x, pii p) {
  if (p.first < 0) return false;
  return p.first <= x && x <= p.second;
}

bool ok(int x, int y, int min_x, int max_x, int min_y, int max_y) {
  return min_x <= x && x <= max_x && min_y <= y && y <= max_y;
}

int main() {
  int n;
  {
    int x, y;
    scanf("%d%d%d", &n, &x, &y);
    for (int i = 1; i <= n; i++) {
      scanf("%d%d%d%d", &min_x[i], &max_x[i], &min_y[i], &max_y[i]);
      min_x[i] -= x;
      max_x[i] -= x;
      min_y[i] -= y;
      max_y[i] -= y;
    }
  }
  for (int i = 0; i <= n; i++) {
    for (int j = 0; j <= n; j++) {
      dp[i][j] = pii(-1, -1);
    }
  }
  dp[0][0] = pii(0, 0);
  for (int i = 0; i < n; i++) {
    for (int j = 0; j <= n; j++) {
      if (dp[i][j].first < 0) continue;
      if (j >= min_y[i + 1] && j <= max_y[i + 1]) {
        pii intersect =
            range_intersect(dp[i][j], pii(min_x[i + 1], max_x[i + 1]));
        if (intersect.first >= 0) {
          dp[i + 1][j + 1] = range_union(dp[i + 1][j + 1], intersect);
          dp[i + 1][j] = range_union(
              dp[i + 1][j], pii(intersect.first + 1, intersect.second + 1));
        } else {
          dp[i + 1][j] = range_union(dp[i + 1][j], dp[i][j]);
        }
      } else {
        dp[i + 1][j] = range_union(dp[i + 1][j], dp[i][j]);
      }
    }
  }
  int ans = 0;
  for (int i = 0; i <= n; i++) {
    if (dp[n][i].first >= 0) {
      ans = max(ans, i + dp[n][i].second);
    }
  }
  printf("%d\n", ans);
}