consider the following algorithm which takes an array A$[0...$n$-1]$ of n numbers:

Algorithm

answer$<-$true

for i$<-0$ to n$-1$ do:

for j$<-$i$+1$ to n$-1$ do:

if A$[$i$]=$ A$[$j$]$ then answer $<-$ false

describe a more efficient algorithm for this problem and indicate its complexity