import java.util.*;

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