| t | import math | t | import math | 
             |  |  |  | 
             | def cross_product(o, a, b): |  | def cross_product(o, a, b): | 
             |     return (a[0] - o[0]) * (b[1] - o[1]) - (a[1] - o[1]) * (b[0] - o[0]) |  |     return (a[0] - o[0]) * (b[1] - o[1]) - (a[1] - o[1]) * (b[0] - o[0]) | 
             |  |  |  | 
             | def is_convex_polygon(points): |  | def is_convex_polygon(points): | 
             |     if len(points) < 3: |  |     if len(points) < 3: | 
             |         return False |  |         return False | 
             |     start = min(points, key=lambda p: (p[1], p[0])) |  |     start = min(points, key=lambda p: (p[1], p[0])) | 
             |     points.remove(start) |  |     points.remove(start) | 
             |     points.sort(key=lambda p: (math.atan2(p[1] - start[1], p[0] - start[ |  |     points.sort(key=lambda p: (math.atan2(p[1] - start[1], p[0] - start[ | 
             | 0]), p[0], p[1])) |  | 0]), p[0], p[1])) | 
             |     points.insert(0, start) |  |     points.insert(0, start) | 
             |     hull = [points[0], points[1]] |  |     hull = [points[0], points[1]] | 
             |     for i in range(2, len(points)): |  |     for i in range(2, len(points)): | 
             |         while len(hull) > 1 and cross_product(hull[-2], hull[-1], points |  |         while len(hull) > 1 and cross_product(hull[-2], hull[-1], points | 
             | [i]) <= 0: |  | [i]) <= 0: | 
             |             hull.pop() |  |             hull.pop() | 
             |         hull.append(points[i]) |  |         hull.append(points[i]) | 
             |     if len(hull) == len(points): |  |     if len(hull) == len(points): | 
             |         return True |  |         return True | 
             |     return False |  |     return False | 
             |  |  |  | 
             | def main(): |  | def main(): | 
             |     points = [] |  |     points = [] | 
             |     while True: |  |     while True: | 
             |         line = input().strip() |  |         line = input().strip() | 
             |         if not line: |  |         if not line: | 
             |             break |  |             break | 
             |         x, y = map(int, line.split(',')) |  |         x, y = map(int, line.split(',')) | 
             |         points.append((x, y)) |  |         points.append((x, y)) | 
             |     if is_convex_polygon(points): |  |     if is_convex_polygon(points): | 
             |         print(True) |  |         print(True) | 
             |     else: |  |     else: | 
             |         print(False) |  |         print(False) | 
             | main() |  | main() |