Directions: Write a main program to test the three functions described below. Input is from a file, and output is to a file. 1. The function processes a string containing letters of the alphabet, which is a parameter. Another parameter is a char variable with a letter value. The function outputs the number of times the char value appears in the string. 2. This Boolean function has two string parameters. It returns true when the first string is a substring of the second string, otherwise it returns false. 3. The input is on one line in an input file, and has up to seven components with a colon (:) at the end of each component. The function separates each component into separate strings (without the colon), and outputs each separated string along with its length. In the output file, use one line for each separated string. One input sample could be George:April:May:William:Johnny: Another input could be Red:Fuscia:Magenta: A third input example is (note internal spaces) Hello, there.:How are you?:Im fine.:Lets go out to dinner