题目描述
题目标题：
校赛-A:Valid Pop Sequence
题目描述：
In computer science, a stack is a last in, first out (LIFO) abstract data type and linear data structure. A stack can have any abstract data type as an element, but is characterized by two fundamental operations, called push and pop. The push operation adds a new item to the top of the stack.
Assume k integers is pushing into a stack in increasing order 1, 2, …, k. Please write a program that decides whether it is a valid pop sequence. For example, pushing 1, 2, 3 into a stack, (1, 2, 3) and (3, 2, 1) is a valid pop sequence, but (3, 1, 2) isn’t.
输入描述：
The input consists of several test cases.
For each test case, one integer k (1 <= k <= 100000) is given in the first line.
Second line contains k integers, presenting a pop sequence.
输出描述描述：
If the pop sequence is valid, print a line contains My Dearest. Otherwise it contains The Everlasting Guilty Crown
样式输入：
3
1 2 3
3
3 1 2
样式输出：
My Dearest
The Everlasting Guilty Crown
熟悉栈的特性就好做了，用数组模拟堆栈就可以了（因为是从1到k递增，不用数组也行）。正序输出是队列，逆序输出是栈，满足这两个条件就是符号条件的。
代码如下：
#include <iostream>
using namespace std;
int main()
{
int i,k;
int t,flag = 1;
cin >> k;
for(i=0;i<k;i++)
{
cin >> t;
if(t == i+1 || t == k-i)
continue;
else
flag = 0;
}
if(flag == 1)
cout << "My Dearest";
else
cout << "The Everlasting Guilty Crown";
return 0;
}