Counting in a While Loop:
Whenever it is not known ahead of the time how many values will be entered into the script, it is often essential to count the number of values which are entered. For illustration, if numbers are read into the script, and then the average of the numbers is preferred, the script should add them together, and keep the track of how many there are, in order to compute the average. The variation below on the script counts the number of numbers which the user successfully enters: