Grid Grid
Time Limit: 1 sec
Memory Limit: 256 MB
Attempts: 64
Accuracy: 43.75%
Author: Akashdeep Goel
There is a N*M grid . Each cell in grid is either #
or * .# indicates that this position is filled
and * indicates empty positions .
You want to color empty position .You can choose a X*Y sub-grid in which all elements are empty and color it .
You have to tell if all the empty elements of the grid can be colored or not .
Print YES or NO.
INPUT
First line contains integer N and M .
Second line contains integer X and Y .
Next N lines contains string of M length .
OUTPUT
Print YES or NO .
Constraints
1<=N,M,X,Y<= 1000 .
X<=N,Y<=M .
EXAMPLE
Input
5 5
3 2
#**##
****#
****#
****#
**###
Output
YES
ID
SUBMITTED AT
STATUS
LANGUAGE
TIME
MEMORY USED
USER
TIME
STATUS
LANGUAGE
TIME
MEMORY USED