The Captains Rooms no. | HackerRank Solution

 This problems belongs to  sets although but for solving this we have to  store room numbers

inside the list or related  structure cause sets default remove duplicate items we can not use it to  store for

after processing counter occurrence  this problems follow sets as theoretically.

Problem:https://www.hackerrank.com/challenges/py-the-captains-room/problem?isFullScreen=true

Code:

# Enter your code here. Read input from STDIN. Print output to STDOUT

k = int(input())

room_nos = list(map(int, input().split()))

from collections import Counter

counts = Counter(room_nos)

for room, count in counts.items():

    if count == 1:

        print(room)

        break

Inpt:

5
1 2 3 6 5 4 4 2 5 3 6 1 6 5 3 2 4 1 2 5 1 4 3 6 8 4 3 1 5 6 2 

Output:

8

Explanation

The list of room numbers contains  elements. Since  is , there must be  groups of families. In the given list, all of the numbers repeat  times except for room number .
Hence,  is the Captain's room number.