b) Write a program which accepts two strings as input and outputs a third string which is made up of the letters, that the input strings have in common (10 Marks) c) Write a program to accept in a string which is no more than 80 characters. Swap the first half of the string with the second half and print out the result. For example: Input String There is a cat sitting on the roof Output tting on the roof There is a cat si (15 Marks)