func_code_string: #include <bits/stdc++.h>   using namespace std;   char str[110];   void in(long long &x, long long &y) {     scanf( %s , str);     int len = strlen(str);     int at;     for (int i = 0; i < len; i++)       if (str[i] ==  / ) at = i;     x = 0;     for (int i = 0; i < at; i++) x = x * 10 + (str[i] -  0 );     y = 0;     for (int i = at + 1; i < len; i++) y = y * 10 + (str[i] -  0 );   }   struct Point {     long long x, y;     void in() { scanf( %I64d %I64d , &x, &y); }   } p[100010], q[100010];   bool cmp_y(Point a, Point b) { return a.y > b.y; }   struct Node {     long long up, down;     int id;     bool operator==(Node a) { return up * a.down == down * a.up; }   } e[100010];   bool cmp(Node a, Node b) { return a.up * b.down < b.up * a.down; }   Point mark[100010];   int X[100010];   int Y[100010];   int totalx, totaly;   int max_value[100010 * 4];   void pushup(int rt) {     max_value[rt] = max(max_value[rt << 1], max_value[rt << 1 | 1]);   }   void update(int pos, int s, int l, int r, int rt) {     if (l == r) {       max_value[rt] = max(max_value[rt], s);       return;     }     int m = (l + r) / 2;     if (pos <= m)       update(pos, s, l, m, rt << 1);     else       update(pos, s, m + 1, r, rt << 1 | 1);     pushup(rt);   }   int query(int L, int R, int l, int r, int rt) {     if (R == 0) return 0;     if (L <= l && r <= R) return max_value[rt];     int m = (l + r) / 2;     int tmp = 0;     if (L <= m) tmp = max(tmp, query(L, R, l, m, rt << 1));     if (R > m) tmp = max(tmp, query(L, R, m + 1, r, rt << 1 | 1));     return tmp;   }   int pp[100010];   int qq;   int main() {     int n;     scanf( %d , &n);     long long Ax, Ay, Bx, By;     in(Ax, Ay);     in(Bx, By);     int m = 0;     for (int i = 0; i < n; i++) {       p[i].in();       if (Ax * p[i].x >= Ay * p[i].y || Bx * p[i].x <= By * p[i].y) continue;       q[m++] = p[i];     }     if (m == 0 || Ay == 0 || Bx == 0) {       printf( 0 n );       return 0;     }     n = m;     for (int i = 0; i < n; i++) p[i] = q[i];     for (int i = 0; i < n; i++) {       e[i].id = i;       e[i].up = p[i].y * Ay - p[i].x * Ax;       e[i].down = Ay;     }     sort(e, e + n, cmp);     totalx = 0;     X[e[0].id] = ++totalx;     for (int i = 1; i < n; i++) {       if (e[i] == e[i - 1])         X[e[i].id] = X[e[i - 1].id];       else         X[e[i].id] = ++totalx;     }     for (int i = 0; i < n; i++) {       e[i].id = i;       e[i].up = p[i].y * By - p[i].x * Bx;       e[i].down = By;       if (By == 0) {         e[i].up = -p[i].x;         e[i].down = 1;       }     }     sort(e, e + n, cmp);     totaly = 0;     Y[e[0].id] = ++totaly;     for (int i = 1; i < n; i++) {       if (e[i] == e[i - 1])         Y[e[i].id] = Y[e[i - 1].id];       else         Y[e[i].id] = ++totaly;     }     for (int i = 0; i < n; i++) mark[i].x = X[i], mark[i].y = Y[i];     sort(mark, mark + n, cmp_y);     memset(max_value, 0, sizeof(max_value));     int ans = 0;     int j = 0;     for (int i = 0; i < n; i = j) {       for (j = i; j < n; j++)         if (mark[i].y != mark[j].y) break;       for (int k = i; k < j; k++) {         int tmp = query(1, mark[k].x - 1, 1, n, 1) + 1;         ans = max(ans, tmp);         pp[k] = tmp;       }       for (int k = i; k < j; k++) update(mark[k].x, pp[k], 1, n, 1);     }     printf( %d n , ans);     return 0;   }   