Codeforces-B-Game with string(模拟栈)

最新推荐文章于 2024-08-07 02:12:39 发布

原创最新推荐文章于 2024-08-07 02:12:39 发布 · 484 阅读

0 ·

CC 4.0 BY-SA版权

思维题同时被 2 个专栏收录

67 篇文章

订阅专栏

codefores水题

58 篇文章

订阅专栏

本文介绍了一个基于字符串操作的游戏策略分析，两个玩家通过删除字符串中连续重复的字符进行博弈，目标是使对手无法操作。文章详细解释了使用栈数据结构解决此问题的方法，并提供了一段C++代码实现。

摘要生成于 C知道，由 DeepSeek-R1 满血版支持，前往体验 >

Two people are playing a game with a string ss, consisting of lowercase latin letters.

On a player's turn, he should choose two consecutive equal letters in the string and delete them.

For example, if the string is equal to "xaax" than there is only one possible turn: delete "aa", so the string will become "xx". A player not able to make a turn loses.

Your task is to determine which player will win if both play optimally.

Input

The only line contains the string ss, consisting of lowercase latin letters (1≤|s|≤100000), where |s||s| means the length of a string ss.

Output

If the first player wins, print "Yes". If the second player wins, print "No".

Examples

input

Copy

abacaba

output

Copy

No

input

Copy

iiq

output

Copy

Yes

input

Copy

abba

output

Copy

No

Note

In the first example the first player is unable to make a turn, so he loses.

In the second example first player turns the string into "q", then second player is unable to move, so he loses.

思路：我们可以用栈来很好的表示这个过程，如果要入栈的字符和栈顶不一样，我们则将该元素压入栈中，如果要压入的元素和栈顶元素相同，我们则让栈顶元素出栈，但这个过程一定要满足栈不为空

代码：

#include<cstdio>
#include<iostream>
#include<algorithm>
#include<cstring>
#include<stack>

using namespace std;
char a[1000005];
stack<char> s;
int main()
{
	
	
	scanf("%s",a);
	int len=strlen(a);
	s.push(a[0]);
	int sum=0;
	for(int t=1;t<len;t++)
	{
		if(!s.empty()&&a[t]==s.top())
		{
			s.pop();
			sum++;
			continue;
		}
		else
		{
			s.push(a[t]);
		}
	 } 
	 if(sum%2==0)
	 {
	 	cout<<"No"<<endl;
	 }
	 else
	 {
	 	cout<<"Yes"<<endl;
	 }

	return 0;
}