Below test cases helped me to check the program:

2 3
.**|_|**.
**.|_|***
ans: [good test]
POBEDA
1A
2C
1F

5 6
...|_|***
...|_|***
...|_|***
...|_|***
...|_|***
ans:
POBEDA
1A
1C
3A
3C
5A
5C

5 12
...|_|...
...|_|...
...|_|...
...|_|...
...|_|...
ans:
POBEDA
1A
1C
3A
3C
5A
5C
1D
1F
3D
3F
5D
5F


6 6
*..|_|***
...|_|***
...|_|***
...|_|***
*..|_|***
..*|_|***
ans:
POBEDA
1C
2A
3C
4A
5C
6A


6 6
*..|_|***
..*|_|***
...|_|***
...|_|***
*..|_|***
...|_|***
ans:
POBEDA
1C
2A
3C
4A
5C
6A


6 6
*..|_|***
*.*|_|***
...|_|***
...|_|***
*..|_|***
...|_|***
ans:
PORAZHENIE