Using C$++$

Goal: Learn how to search for a value in an array.

Assignment: Assume a randomly ordered array of$$int$,$ of size$$n$.$ The array$$arr$$contains the integers from $0$ to n$,$ except for one integer missing. For example,$$arr$=\{3,0,1,4,5\}$is missing the number $2.$

Write a function$$findMissingNumber$()$which takes as parameters the array$$arr$[]$as well as the int$$n$,$ and returns the integer missing from the array.

Note:$$The$$swap$$function has already been defined and is available to be called from your code.

Hint:$$First$,$ sort the array. Then step through the array looking for the missing number.