In this **HackerRank Introduction to sets problem solution in python**, A set is an unordered collection of elements without duplicate entries.

When printed, iterated or converted into a sequence, its elements will appear in an arbitrary order.

Now, let’s use our knowledge of sets and help Mickey.

Ms. Gabriel Williams is a botany professor at District College. One day, she asked her student Mickey to compute the average of all the plants with distinct heights in her greenhouse.

## Problem solution in Python 2 programming.

n = float(raw_input()) plant = set() sum_p = 0 for x in raw_input().split(' '): if x not in plant: plant.add(x) sum_p += float(x) print sum_p/float(len(plant))

## Problem solution in Python 3 programming.

def average(array): return sum(set(array))/len(set(array))

### Problem solution in pypy programming.

def average(array): s = set(array) return sum(s)/len(s)

### Problem solution in pypy3 programming.

def average(array): # your code goes here x=set(array) return float(sum(x)/len(x))