huckleberry% cc201 roberts.c
huckleberry% 

huckleberry% a.out
Enter an integer: 3
n = 3
huckleberry% 

huckleberry% a.out
Enter an integer: a
Please enter an integer
Retry: b
Please enter an integer
Retry: 17.2
Unexpected character: '.'
Retry: 100  abc
Unexpected character: 'a'
Retry: 100
n = 100
huckleberry%