There are six singers: F, G, L, K, H, M  Three piano accompaniment: X, Y, W  Each piano accompanist happens to accompany two of the singers  The known conditions are as follows: (1) if X accompanies F, W accompanies L  (2) if X does not accompany G, Y accompanies M  (3) X or Y to accompany H
(4) F and G do not share the same accompanist; L and K do not share the accompanist; H and M do not share the accompanist
X is the accompaniment of F and H, Y is the accompaniment of L and M, and W is the accompaniment of G and K.