A bit string is a string consisting of only 0's and 1's. Consider the following recursive definition of the function "count", which counts the number of 1's in the bitstring: Base case: count(elementof) = 0 Recursive case 1: count(1 middot s) = 1 + count (s) Recursive case 2: count(0 middot s) = count (s) Use structural induction to prove that count(st) = count (s) + count (t)