A Padovan string P(n) for a natural number n is defined as: P(0) = ‘X’ P(1) = ‘Y’ P(2) = ‘Z’ P(n) = P(n-2) + P(n-3), n>2 where + denotes string concatenation. For a string of the characters ‘X’ , ‘Y’ and ‘Z’ only, and given value of n, write a program that counts the number of occurrences of the string in the n-th Padovan string P(n). An example is given below. For n = 6 and the string ZY, the program should count the occurrences of ZY in P(6). P(0) = ‘X’ P(1) = ‘Y’ P(2) = ‘Z’ P(n) = P(n-2) + P(n-3), n>2 P(3) = P(1)+P(0) P(3) = YX P(4) = P(2)+P(1) P(4) = ZY P(5) = P(3)+P(2) P(5) = YXZ P(6) = P(4)+P(3) P(6) = ZYYX