33 lines
778 B
Java
33 lines
778 B
Java
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# 30. 包含 min 函数的栈
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[NowCoder](https://www.nowcoder.com/practice/4c776177d2c04c2494f2555c9fcc1e49?tpId=13&tqId=11173&tPage=1&rp=1&ru=/ta/coding-interviews&qru=/ta/coding-interviews/question-ranking&from=cyc_github)
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## 题目描述
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定义栈的数据结构，请在该类型中实现一个能够得到栈最小元素的 min 函数。
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## 解题思路
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```java
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private Stack<Integer> dataStack = new Stack<>();
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private Stack<Integer> minStack = new Stack<>();
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public void push(int node) {
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dataStack.push(node);
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minStack.push(minStack.isEmpty() ? node : Math.min(minStack.peek(), node));
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}
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public void pop() {
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dataStack.pop();
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minStack.pop();
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}
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public int top() {
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return dataStack.peek();
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}
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public int min() {
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return minStack.peek();
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}
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```
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