17a.c

   1 #include <stdio.h>
   2 #include <stdbool.h>
   3
   4 bool is_in(int dx, int dy, int x1, int x2, int y1, int y2, int *maxy)
   5 {
   6         int x = 0, y = 0, my = 0;
   7         while (y >= y1 && x <= x2) {
   8                 x+=dx;
   9                 y+=dy;
  10                 my = y > my ? y : my;
  11                 dx = dx == 0 ? 0 : dx-1;
  12                 dy--;
  13                 if (x >= x1 && x <= x2 && y >= y1 && y <= y2) {
  14                         *maxy = my > *maxy ? my : *maxy;
  15                         return true;
  16                 }
  17         }
  18         return false;
  19 }
  20
  21 int main()
  22 {
  23         int x1, x2, y1, y2, maxy = 0;
  24         scanf("target area: x=%d..%d, y=%d..%d\n", &x1, &x2, &y1, &y2);
  25         for (int dy = x2; dy >= 0; dy--)
  26                 for (int dx = 1; dx <= x2; dx++)
  27                         if (is_in(dx, dy, x1, x2, y1, y2, &maxy))
  28                                 break;
  29         printf("%d\n", maxy);
  30 }