C$++$

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.

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