Leetcode 155 Min Stack
Leetcode 155 Min Stack
triplebee
发布于 2018-01-12 14:51:24
发布于 2018-01-12 14:51:24
Design a stack that supports push, pop, top, and retrieving the minimum element in constant time.
- push(x) -- Push element x onto stack.
- pop() -- Removes the element on top of the stack.
- top() -- Get the top element.
- getMin() -- Retrieve the minimum element in the stack.
Example:
MinStack minStack = new MinStack();
minStack.push(-2);
minStack.push(0);
minStack.push(-3);
minStack.getMin(); --> Returns -3.
minStack.pop();
minStack.top(); --> Returns 0.
minStack.getMin(); --> Returns -2.模拟实现栈，求取栈中的最小值的方法非常巧妙，可以仔细琢磨琢磨。
class MinStack {
public:
/** initialize your data structure here. */
stack<int> s1,s2;
MinStack() {
}
void push(int x) {
s1.push(x);
if(s2.empty() || x <= s2.top()) s2.push(x);
}
void pop() {
if(s1.top() == s2.top()) s2.pop();
s1.pop();
}
int top() {
return s1.top();
}
int getMin() {
return s2.top();
}
};
/**
* Your MinStack object will be instantiated and called as such:
* MinStack obj = new MinStack();
* obj.push(x);
* obj.pop();
* int param_3 = obj.top();
* int param_4 = obj.getMin();
*/本文参与 腾讯云自媒体分享计划，分享自作者个人站点/博客。
原始发表：2016-12-29 ，如有侵权请联系 cloudcommunity@tencent.com 删除
评论
登录后参与评论
推荐阅读