mediummath 10 XP per passing test

Find the Missing Number

Name: PrepSync
Rating: 4.9 (120 reviews)

Problem

Given a list of numbers from 1 to n, find the missing number. The list can contain duplicates and negative numbers. The input is given on two lines: the first line contains the size of the list and the second line contains the list of numbers. The output should be the missing number.

Sample input

Output

(run your code to see output)