You are given the following algorithm:

Algorithm whatIsThis$($A$[0...$n$-1])$

mergesort$($A$)$

i $0$

while i $<$ n do

while i $<$ n$-1$ and A$[$i$]=$ A$[$i$+1]$ do

i $$ i $+1$

B$[$i$]$ A$[$i$]$

i $$ i $+1$

return B

a$.$ What is the purpose of this algorithm?

b$.$ There is one logical error in this algorithm. Find and correct it$.$

c$.$ What is the complexity of this algorithm? Explain your reasoning.