#include <bits/stdc++.h>
using namespace std;

const int N = 140005;

int i, j, k, h, w, n, rs, x, y, ans[4 * N], totalSum[4 * N];
pair<int, int> a[N];

int goToNext(int x, int i) {
  for(++i; i <= n && a[i].first == x; ++i);
  return i;
}

void update(int left, int right, int nod) {
  if(left == right) {
    totalSum[nod] += y;
    ans[nod] = totalSum[nod];
  } else {
    int pivot = (left + right) / 2;
    if(x <= pivot) update(left, pivot, 2 * nod);
    else update(pivot + 1, right, 2 * nod + 1);
    totalSum[nod] = totalSum[2 * nod] + totalSum[2 * nod + 1];
    ans[nod] = max(ans[2 * nod], totalSum[2 * nod] + ans[2 * nod + 1]);
  }
}

int main() {
  freopen("mine.in", "r", stdin);
  freopen("mine.out", "w", stdout);

  scanf("%d %d %d", &h, &w, &n);
  for(i = 1; i <= n; ++i) scanf("%d %d", &a[i].first, &a[i].second), a[i].first += 30001, a[i].second += 30001;

  sort(a + 1, a + n + 1);

  for(j = i = 1; i <= n; ++i) {
    x = 2 * a[i].second - 1; y = 1; update(1, N - 1, 1);
    x = 2 * (a[i].second + w); y = -1; update(1, N - 1, 1);
    while(a[i].first - a[j].first > h) {
      x = 2 * a[j].second - 1; y = -1; update(1, N - 1, 1);
      x = 2 * (a[j].second + w); y = 1; update(1, N - 1, 1);
      ++j;
    }
    rs = max(rs, ans[1]);
  }

  printf("%d\n", rs);

  return 0;
}