用栈模拟汉诺塔问题

yingl · yingl · commit 8f2cd32ac1dc · 2016-09-23T14:22:12.000+08:00
diff --git a/mock_hanoi_tower_by_stacks.py b/mock_hanoi_tower_by_stacks.py
@@ -0,0 +1,44 @@
+class Tower(object):
+    # create three towers (i from 0 to 2)
+    def __init__(self, i):
+        self.disks = []
+  
+    # Add a disk into this tower
+    def add(self, d):
+        if len(self.disks) > 0 and self.disks[-1] <= d:
+            print "Error placing disk %s" % d
+        else:
+            self.disks.append(d);
+  
+    # @param {Tower} t a tower
+    # Move the top disk of this tower to the top of t.
+    def move_top_to(self, t):
+        # Write your code here
+        if len(self.disks) > 0:
+            t.disks.append(self.disks.pop())
+  
+    # @param {int} n an integer
+    # @param {Tower} destination a tower
+    # @param {Tower} buffer a tower
+    # Move n Disks from this tower to destination by buffer tower
+    def move_disks(self, n, destination, buffer):
+        # Write your code here
+        if n == 0:
+            return
+        elif n == 1:
+            self.move_top_to(destination)
+        else:
+            self.move_disks(n - 1, buffer, destination)
+            self.move_top_to(destination)
+            buffer.move_disks(n - 1, destination, self)
+
+    def get_disks(self):
+        return self.disks
+
+"""
+Your Tower object will be instantiated and called as such:
+towers = [Tower(0), Tower(1), Tower(2)]
+for i in xrange(n - 1, -1, -1): towers[0].add(i)
+towers[0].move_disks(n, towers[2], towers[1])
+print towers[0], towers[1], towers[2]
+"""
