TwoPointerGarbageCollection

# Problem Statement:
#
# You are designing a basic garbage collection algorithm class.
#
# The goal of the class is to output an modified version of the input array containing 
# references to live objects, the remainder of objects will later be cleared by a function that 
# trims all the values 
#
# Implement a function that returns a modified array containing a continous sub array of
# live objects and their indices so that all dead objects can be chopped off by the garbage collector.
# 
# You may not use any additional array space.
#
# Input 
#   arr [o1(live), o2(dead), o3(live), o4(dead), o5(dead)]
#
# Output 
#   arr [{o1,o3},o3,o4,o5]; {} denotes the live objects  
#   sub arr index: [0,1]
#
# Extension: 
#   We can no longer assume the first object will be alive 
#   Adjust the algorithm to handle this
# 
# Input 
#   arr [o1(dead), o2(live), o3(dead), o4(live), o5(dead)]
#
# Output 
#   arr [o1,{o2,o4},o4,o5]; 
#   sub arr index: [1,2]
#
# Class: Two Pointers