A C++ implementation of Breadth First Search. CSC 325 - Algorithms

Read one or more pairs of wrestler names from standard input. Names are separated by whitespace, so you can read them as strings using the normal >> operator. Each pair represents a rivalry. You can assume that the “rivalry graph” represented by the input is connected. Here is a sample input:

fang sally  
shorty zephyr  
the_machine big_earl  
percival shorty  
fang the_machine  
sally shorty  

You must use a single breadth-first search to determine if the wrestlers can be partitioned into babyfaces and heels. (Hint: BFS/distances/even-odd.) To ensure that the output is unique, you must use the first wrestler in the first rivalry as the source for the breadth-first search; that first wrestler must be designated a babyface if a partition exists. Output the babyfaces and heels in sorted order to standard output, using the exact formats shown below.

BABYFACES  
big_earl  
fang  
shorty  
HEELS  
percival  
sally  
the_machine  
zephyr  

A partition exists for this sample input but may not exist in general. If no partition exists, output the following single line:
IMPOSSIBLE