7! = 1 x 2 x 3 x 4 x 5 x 6 x 7 = 5,840 Write a program that lets the user enter a nonnegative integer and then uses a for-loop to calculate the factorial of that number. Print the factorial to standard output. SAMPLE RUN #1 Enter a nonnegative integer: 7 7 factorial is 5040 SAMPLE RUN #2 Enter a nonnegative integer: 1 1 factorial is 1 SAMPLE RUN #3 Enter a nonnegative integer: 10 -10 is not a nonnegative integer