A character wave consistss of lines of characters, which has a parameter, length L. The number of characters in the first line is 1, and is increased by one in the every following lines. After the number of character reaches L, it starts to descrease until the number of characters become 1 again. For example, the following is a character wave of length 3.
#
##
###
##
#
There are two items, separated by a space: the first one is a character C; the second one specifies the length L.