Virtual contest is a way to take part in past contest, as close as possible to participation on time. It is supported only ACM-ICPC mode for virtual contests.
If you've seen these problems, a virtual contest is not for you - solve these problems in the archive.
If you just want to solve some problem from a contest, a virtual contest is not for you - solve this problem in the archive.
Never use someone else's code, read the tutorials or communicate with other person during a virtual contest.

This round has an unusual addition to the rules. For each problem you must use distinct language. Thus, if you have a submission that has passed at least one test or is being tested at the moment, then for this task you can use only this language and can not use it for other tasks. More details can be read by the link. Different implementations of the same language are considered to be the same language (for example, in C++ you can only solve one problem, regardless of the exact chosen compiler).

No tag edit access

J. Stepan's Series

time limit per test

2 secondsmemory limit per test

256 megabytesinput

standard inputoutput

standard outputWell, the series which Stepan watched for a very long time, ended. In total, the series had *n* episodes. For each of them, Stepan remembers either that he definitely has watched it, or that he definitely hasn't watched it, or he is unsure, has he watched this episode or not.

Stepan's dissatisfaction is the maximum number of consecutive series that Stepan did not watch.

Your task is to determine according to Stepan's memories if his dissatisfaction could be exactly equal to *k*.

Input

The first line contains two integers *n* and *k* (1 ≤ *n* ≤ 100, 0 ≤ *k* ≤ *n*) — the number of episodes in the series and the dissatisfaction which should be checked.

The second line contains the sequence which consists of *n* symbols "Y", "N" and "?". If the *i*-th symbol equals "Y", Stepan remembers that he has watched the episode number *i*. If the *i*-th symbol equals "N", Stepan remembers that he hasn't watched the epizode number *i*. If the *i*-th symbol equals "?", Stepan doesn't exactly remember if he has watched the episode number *i* or not.

Output

If Stepan's dissatisfaction can be exactly equal to *k*, then print "YES" (without qoutes). Otherwise print "NO" (without qoutes).

Examples

Input

5 2

NYNNY

Output

YES

Input

6 1

????NN

Output

NO

Note

In the first test Stepan remembers about all the episodes whether he has watched them or not. His dissatisfaction is 2, because he hasn't watch two episodes in a row — the episode number 3 and the episode number 4. The answer is "YES", because *k* = 2.

In the second test *k* = 1, Stepan's dissatisfaction is greater than or equal to 2 (because he remembers that he hasn't watch at least two episodes in a row — number 5 and number 6), even if he has watched the episodes from the first to the fourth, inclusive.

Codeforces (c) Copyright 2010-2018 Mike Mirzayanov

The only programming contests Web 2.0 platform

Server time: Jun/21/2018 21:07:05 (d2).

Desktop version, switch to mobile version.

User lists

Name |
---|