946.验证栈序列 剑指 offer 31.cpp

/*
 * @lc app=leetcode.cn id=946 lang=cpp
 *
 * [946] 验证栈序列
 */
// 自己想出来和 LeetCode 一样的
// 解法为 LeetCode 的解法
// @lc code=start
class Solution {
  public:
    bool validateStackSequences(vector<int> &pushed, vector<int> &popped) {
        stack<int> st;
        int n = pushed.size();
        for (int i = 0, j = 0; i < n; i++) {
            st.emplace(pushed[i]);
            while (!st.empty() && st.top() == popped[j]) {
                st.pop();
                j++;
            }
        }
        return st.empty();
    }
};
// @lc code=end