easy

Find the missing element in a given permutation.

Task description

An array A consisting of N different integers is given. The array contains integers in the range [1..(N + 1)], which means that exactly one element is missing.

Your goal is to find that missing element.

Write a function:

class Solution { public int solution(int[] A); }

that, given an array A, returns the value of the missing element.

For example, given array A such that:

the function should return 4, as it is the missing element.

Write an ** efficient** algorithm for the following assumptions:

- N is an integer within the range [0..100,000];
- the elements of A are all distinct;
- each element of array A is an integer within the range [1..(N + 1)].

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Solution

Programming language used Java

Total time used 1 minutes

Effective time used 1 minutes

Notes
*not defined yet*

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