Design and implement an algorithm that, when given a collection of integers in an unsorted array, determines the third smallest number (or third minimum). For example, if the array consists of the values 21, 3, 25, 1, 12, and 6 the algorithm should report the value 6, because it is the third smallest number in the array. Do not sort the array.
To implement your algorithm, write a function thirdSmallest that receives an array as a parameter and returns the third-smallest number. To test your function, write a program that populates an array with random numbers and then calls your function.