Here is the question:

Write a recursive lookup function to search an array in sorted order. Write a program in C to test your function. Use random() to fill array a[] of size n, and use bubble_sort() to sort the array. The function call look_up(v, a, n) should be used to look for the value v in the array a[]. If just one of the elements of the array, say a[i] has the value v, then i should be returned. If two or more of the elements of the array have the value v, then the index of any one of them in an acceptable answer.

Can someone point me in the right direction on where to start? Thank you.