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最新推荐文章于 2021-11-23 14:00:42 发布

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King of Thieves

Time Limit: 1000ms

Memory Limit: 262144KB

This problem will be judged on CodeForces. Original ID: 526A
64-bit integer IO format: %I64d Java class name: (Any)

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In this problem you will meet the simplified model of game King of Thieves.

In a new ZeptoLab game called "King of Thieves" your aim is to reach a chest with gold by controlling your character, avoiding traps and obstacles on your way.

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An interesting feature of the game is that you can design your own levels that will be available to other players. Let's consider the following simple design of a level.

A dungeon consists of n segments located at a same vertical level, each segment is either a platform that character can stand on, or a pit with a trap that makes player lose if he falls into it. All segments have the same length, platforms on the scheme of the level are represented as '*' and pits are represented as '.'.

One of things that affects speedrun characteristics of the level is a possibility to perform a series of consecutive jumps of the same length. More formally, when the character is on the platform number i1, he can make a sequence of jumps through the platforms i1 < i2 < ... < ik, if i2 - i1 = i3 - i2 = ... = ik - ik - 1. Of course, all segments i1, i2, ... ik should be exactly the platforms, not pits.

Let's call a level to be good if you can perform a sequence of four jumps of the same length or in the other words there must be a sequence i1, i2, ..., i5, consisting of five platforms so that the intervals between consecutive platforms are of the same length. Given the scheme of the level, check if it is good.

Input

The first line contains integer n (1 ≤ n ≤ 100) — the number of segments on the level.

Next line contains the scheme of the level represented as a string of n characters '*' and '.'.

Output

If the level is good, print the word "yes" (without the quotes), otherwise print the word "no" (without the quotes).

Sample Input

Input

16
.**.*..*.***.**.

Output

yes

Input

11
.*.*...*.*.

Output

no

暴力无误题意就是是否存在5个＊的下标能构成等差数列

#include <stdio.h>
#include "stdio.h"

int main()
{
    int m;
    char ss[102];
    scanf("%d",&m);
    scanf("%s",ss+1);
    for(int i=1;i<=m;i++)
        for(int j=1;j<=m/4;j++)
            if(ss[i]=='*'&&ss[i+j]=='*'&&ss[i+j*2]=='*'&&ss[i+j*3]=='*'&&ss[i+j*4]=='*'){
                printf("yes\n");
                return 0;
            }
    printf("no\n");
    return 0;
}