Please use C

White and Black Horse Lili was very glad when playing chess. She also very interested especially on knight piece. The, she decided to find some fact from the knight piece. Apparently, the black knight and white knight are couple. Because Lili knows the truth, she will try to bring them together. But because Lili is a beginner player in chess, she can only run each piece N times. Help Lili find out whether the two knights (the white and the black one) can meet together or not. You are encouraged to use recursive techniques to solve this problem. Format Input Input consists of 1 integer T indicating number of testcase and followed by 2T row after. For each test case, the first line contains N , number of step limitation in this game. The second line contains the coordinate (in chessboard) x1, y1, location of the black knight and the coordinate (in chessboard) x2, y2, location of the white knight. Coordinates will be expressed in letter and number form (e.g. A5, A2, C1). Format Output Output should be expressed in format Case #X: Y - X is number of testcase (staring from 1) and Y is the answer YES if those two knights can meet together and NO if they can not meet together (without quotes).

Constraints 1 T, N 10 A x1, x2 H 1 y1, y2 8 Sample Input (standard input) 2 3 A1 H8 1 H1 A8 Sample Output (standard output) Case #1: YES Case #2: NO Explanation The possible way for them to meet each other described on the figure above. Steps for the black knight is colored yellow and for the white knight is colored red. Finally, they meet together in a purple area. Note For this problem, there are many possibilities those knights can meet at various points. So as long as they can meet together, the output will be YES, even though there is only 1 valid point.