game design

Author: idf

353 Design Snake Game.py

@@ -0,0 +1,67 @@
+"""
+Design a Snake game that is played on a device with screen size = width x height.
+"""
+from collections import deque
+
+__author__ = 'Daniel'
+
+
+class SnakeGame(object):
+    def __init__(self, width, height, food):
+        """
+        Initialize your data structure here.
+        @param width - screen width
+        @param height - screen height
+        @param food - A list of food positions
+        E.g food = [[1,1], [1,0]] means the first food is positioned at [1,1], the second is at [1,0].
+        :type width: int
+        :type height: int
+        :type food: List[List[int]]
+        """
+        self.w = width
+        self.h = height
+        self.food = deque(food)
+        self.body = deque([(0, 0)])
+        self.dirs = {
+            'U': (-1, 0),
+            'L': (0, -1),
+            'R': (0, 1),
+            'D': (1, 0),
+        }
+        self.eat = 0
+
+    def move(self, direction):
+        """
+        Moves the snake.
+        @param direction - 'U' = Up, 'L' = Left, 'R' = Right, 'D' = Down
+        @return The game's score after the move. Return -1 if game over.
+        Game over when snake crosses the screen boundary or bites its body.
+        :type direction: str
+        :rtype: int
+        """
+        x, y = self.body[0]
+        dx, dy = self.dirs[direction]
+        x += dx
+        y += dy
+        fx, fy = self.food[0] if self.food else (-1, -1)
+        if x == fx and y == fy:
+            self.food.popleft()
+            self.eat += 1
+        else:
+            self.body.pop()
+            if (x, y) in self.body or not (0 <= x < self.h and 0 <= y < self.w):
+                # possible to use set to accelerate check
+                return -1
+
+        self.body.appendleft((x, y))
+        return self.eat
+
+
+# Your SnakeGame object will be instantiated and called as such:
+# obj = SnakeGame(width, height, food)
+# param_1 = obj.move(direction)
+
+if __name__ == "__main__":
+    game = SnakeGame(3, 2, [[1, 2], [0, 1]])
+    for char, expect in zip('RDRULU', [0, 0, 1, 1, 2, -1]):
+        assert game.move(char) == expect