everest% cc scan1.c
everest% 

everest% a.out
Enter 3 integers: 1 2 3
r = 3
a = 1, b = 2, c = 3
everest% 

everest% a.out
Enter 3 integers: 123
4
5
r = 3
a = 123, b = 4, c = 5
everest% 

everest% a.out
Enter 3 integers: 1     2


3
r = 3
a = 1, b = 2, c = 3
everest% 

everest% a.out
Enter 3 integers: 1 abc 2
r = 1
a = 1, b = 0, c = 0
everest% 

everest% a.out 
Enter 3 integers: 17 19 32
r = 3
a = 17, b = 19, c = 32
everest% 

everest% a.out <test
Enter 3 integers: r = 3
a = 7, b = 8, c = 9
everest%