25 lines
488 B
Python
25 lines
488 B
Python
class Stack(object):
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def __init__(self):
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self.items = []
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def __repr__(self):
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return self.items.__repr__()
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def push(self, x):
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self.items.append(x)
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def pop(self):
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if not self.items:
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return None
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return self.items.pop()
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def peek(self):
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if not self.items:
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return None
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return self.items[-1]
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def from_list(xs):
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result = Stack()
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for x in xs:
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result.push(x)
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return result
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