diff options
Diffstat (limited to 'users/wpcarro/scratch/facebook/largest-stack.py')
-rw-r--r-- | users/wpcarro/scratch/facebook/largest-stack.py | 49 |
1 files changed, 49 insertions, 0 deletions
diff --git a/users/wpcarro/scratch/facebook/largest-stack.py b/users/wpcarro/scratch/facebook/largest-stack.py new file mode 100644 index 000000000000..052db44153d4 --- /dev/null +++ b/users/wpcarro/scratch/facebook/largest-stack.py @@ -0,0 +1,49 @@ +from stack import Stack, from_list +from heapq import heapify, heappush, heappop +from random import shuffle + +class MaxStack(Stack): + def __init__(self): + self.max = Stack() + super().__init__() + + def __repr__(self): + return super().__repr__() + + def push(self, x): + super().push(x) + max = self.get_max() + if not max: + self.max.push(x) + else: + self.max.push(max if x < max else x) + + def pop(self): + self.max.pop() + return super().pop() + + def get_max(self): + return self.max.peek() + +xs = list(range(1, 11)) +shuffle(xs) +stack = MaxStack() +for x in xs: + stack.push(x) + +print(stack) +result = stack.get_max() +print(result) +assert result == 10 + +popped = stack.pop() +print("Popped: {}".format(popped)) +print(stack) +while popped != 10: + assert stack.get_max() == 10 + popped = stack.pop() + print("Popped: {}".format(popped)) + print(stack) + +assert stack.get_max() != 10 +print("Success!") |