37 lines
1.3 KiB
Java
37 lines
1.3 KiB
Java
|
# 31. 栈的压入、弹出序列
|
|||
|
|
|
|||
|
|
[NowCoder](https://www.nowcoder.com/practice/d77d11405cc7470d82554cb392585106?tpId=13&tqId=11174&tPage=1&rp=1&ru=/ta/coding-interviews&qru=/ta/coding-interviews/question-ranking&from=cyc_github)
|
|||
|
|
|
|||
|
|
## 题目描述
|
|||
|
|
|
|||
|
|
输入两个整数序列，第一个序列表示栈的压入顺序，请判断第二个序列是否为该栈的弹出顺序。假设压入栈的所有数字均不相等。
|
|||
|
|
|
|||
|
|
例如序列 1,2,3,4,5 是某栈的压入顺序，序列 4,5,3,2,1 是该压栈序列对应的一个弹出序列，但 4,3,5,1,2 就不可能是该压栈序列的弹出序列。
|
|||
|
|
|
|||
|
|
## 解题思路
|
|||
|
|
|
|||
|
|
使用一个栈来模拟压入弹出操作。
|
|||
|
|
|
|||
|
|
```java
|
|||
|
|
public boolean IsPopOrder(int[] pushSequence, int[] popSequence) {
|
|||
|
|
int n = pushSequence.length;
|
|||
|
|
Stack<Integer> stack = new Stack<>();
|
|||
|
|
for (int pushIndex = 0, popIndex = 0; pushIndex < n; pushIndex++) {
|
|||
|
|
stack.push(pushSequence[pushIndex]);
|
|||
|
|
while (popIndex < n && !stack.isEmpty()
|
|||
|
|
&& stack.peek() == popSequence[popIndex]) {
|
|||
|
|
stack.pop();
|
|||
|
|
popIndex++;
|
|||
|
|
}
|
|||
|
|
}
|
|||
|
|
return stack.isEmpty();
|
|||
|
|
}
|
|||
|
|
```
|
|||
|
|
|
|||
|
|
|
|||
|
|
|
|||
|
|
|
|||
|
|
|
|||
|
|
|
|||
|
|
<div align="center"><img width="320px" src="https://cs-notes-1256109796.cos.ap-guangzhou.myqcloud.com/githubio/公众号二维码-1.png"></img></div>
|