Input 
5
.#...
####.
.####
...#.
.....
Output 
YES
Input 
4
####
####
####
####
Output 
NO
Input 
6
.#....
####..
.####.
.#.##.
######
.#..#.
Output 
YES
Input 
6
.#..#.
######
.####.
.####.
######
.#..#.
Output 
NO
Input 
3
...
...
...
Output 
YES