The input consists of several cases, each of which contains two lines.
For each test case, the first line contains 4 integers N, M, L and R (1 <= M <= N <= 30, 0 < L < 100000000, 0 < R < 10000), separated by a single space. N is the number of the footballs, M is the maximum number of footballs one player can shot in one turn, L is the maximum distance that a player can shoot, and R is the radius of footballs.
The next line contains N numbers, S(1), S(2), ..., S(N) (0 < S(i) < 100000000), which describe the distance between footballs and the goal.