You are given a bunch of wooden sticks. Each endpoint of each stick is colored with some color. Is it possible to align the sticks in a straight line such that the colors of the endpoints that touch are of the same color?Input
Input is a sequence of lines, each line contains two words, separated by spaces, giving the colors of the endpoints of one stick. A word is a sequence of lowercase letters no longer than 10 characters. There is no more than 250000 sticks.Output
If the sticks can be aligned in the desired way, output a single line saying Possible, otherwise output Impossible.
blue red red violet cyan blue blue magenta magenta cyan blue red red violet cyan blue blue magenta magenta cyanSample Output
Huge input,scanf is recommended.Source
The UofA Local 2000.10.14