The chess endgame "a king and a queen versus a king" is known to be easy
victory for the side that has a queen.
The position in such an endgame is described by the locations of three figures:
the white king, the white queen, and the black king. Locations are written in a usual
chess notation, constructed from a letter from "a" to "h", which determine vertical
line, and the digit from 1 to 8, which determine horizontal line of the location.
Given the position described, you are find a move for the white queen by
which the black king will be checkmated, or determine that no such a move exists.
Input file format
The input file contains three two-character locations for the white king, white
queen, and black king, in that order, separated by spaces.
The input position is a valid chess position for the white's turn, i.e. all figures
occupy different spaces, kings are not located in the neighboring squares, and the
black king is not under the check.
Output file format
Output file must contain the two-character location - destination square for
the white queen's move. If checkmating move does not exist, output file must contain
the string "no". If there is more than one checkmating move, you may output any one
of them.
