Write a function that accepts a string as argument and returns the number of words contained in the string. For instance, if the string argument is "Four score and seven years ago" the function should return the number 6 because there are six words in that string. Please use a meaningful word for the function name. Demonstrate the function in a program that prompts the user to input a string then passes it to the function. The number of words in the string should be displayed on the screen.

Declare the prototype for the function above the main and implement it below the main.

Hint: Use the get line(cin, str) function to read an entire line as input in the string variable str.