题解 | #栈的压入、弹出序列#

import java.util.*;

public class Solution {
    public boolean IsPopOrder(int [] pushA,int [] popA) {
      int popNum = 0;
      Stack<Integer> stack = new Stack<Integer>();
      for(int i =0; i < popA.length; i++){
        stack.push(pushA[i]);
        while(!stack.empty()&&stack.peek() == popA[popNum]){
            stack.pop();
            popNum++;
        }
      }
      return stack.empty();
    }
}