The printf Function

Now we wish to tell the user what the first of the numbers was that they entered. This is done by inserting a %d in the format string for the printf function on the next line, and following the format string by the name of the variable which contains the number we want to display. Notice that printf does not need to modify the contents of the variable, so we do not need to pass its address. A copy of its contents will suffice, hence no ampersand needs to be used.