剑指Offer31 栈的压入 ，弹出序列

Posted 2021-11-10 小布丁value

栈的压入 ，弹出序列

代码思路：

class Solution {
    public boolean validateStackSequences(int[] pushed, int[] popped) {
        if(pushed==null||pushed.length<0||popped==null||popped.length<0) return false;
        Stack<Integer> stack=new Stack<>();
        int j=0;
        for(int num:pushed){
          stack.push(num);
          while(!stack.isEmpty()&& stack.peek()==popped[j]){
              stack.pop();
             j++;
          }

        }
          return stack.isEmpty();
    }
}