#include <stdio.h>#include <stdlib.h>#define MAX_N 1024struct node { int w, h, k;};struct node in[MAX_N], *sort_h[MAX_N], *sort_k[MAX_N];int A, B, C, N, ch, cw, ans, box, slash, cnt;int cmp_h(const void *a, const void *b){ return (*(struct node **)b)->h - (*(struct node **)a)->h;}int cmp_k(const void *a, const void *b){ return (*(struct node **)b)->k - (*(struct node **)a)->k;}__inline void update(int h, int w){ int k; for ( ; box < N && sort_h[box]->h >= h; box++) if (sort_h[box]->w >= w && sort_h[box]->w <= w + cw) cnt++; k = A * h + B * w + C; for ( ; slash < N && sort_k[slash]->k > k; slash++) if (sort_k[slash]->w >= w && sort_k[slash]->w <= w + cw) cnt--; if (cnt > ans) ans = cnt;}__inline void calc(int i){ int h, w; box = 0; slash = 0; cnt = 0; h = sort_h[i]->h; w = sort_h[i]->w; for ( ; i < N && sort_h[i]->h >= h - ch; i++) if (sort_h[i]->w >= w && sort_h[i]->w <= w + cw) update(sort_h[i]->h, w);}int main(){ int i; scanf("%d%d%d%d", &N, &A, &B, &C); cw = C/B; ch = C/A; for (i = 0; i < N; i++) { scanf("%d%d", &in[i].h, &in[i].w); in[i].k = A * in[i].h + B * in[i].w; sort_h[i] = &in[i]; sort_k[i] = &in[i]; } qsort(sort_h, N, sizeof(sort_h[0]), cmp_h); qsort(sort_k, N, sizeof(sort_k[0]), cmp_k); for (i = 0; i < N; i++) calc(i); printf("%dn", ans); return 0;}
