# If, # comprehensive application of ifdef and # ifndef

1 # include <stdio. h>
2
3 # define MAX
4
5 # define MAXIMUM (x, y) x> y? X: y
6 # define MINIMUM (x, y) x <y? X: y
7
8 int main ()
9 {
10 int a = 10, B = 20;
11
12 # ifdef MAX
13 printf ("\ 40: The larger one is % d \ n", MAXIMUM (a, B ));
14 # else
15 printf ("\ 40: The lower one is % d \ n", MINIMUM (a, B ));
16 # endif
17
18
19 # ifndef MIN
20 printf ("\ 40: The lower is % d \ n", MINIMUM (a, B ));
21 # else
22 printf ("\ 40: The larger one is % d \ n", MAXIMUM (a, B ));
23 # endif
24
25 # undef MAX
26 # ifdef MAX
27 printf ("\ 40: The larger one is % d \ n", MAXIMUM (a, B ));
28 # else
29 printf ("\ 40: The lower one is % d \ n", MINIMUM (a, B ));
30 # endif
31
32
33 # define MIN
34 # ifndef MIN
35 printf ("\ 40: The lower one is % d \ n", MINIMUM (a, B ));
36 # else
37 printf ("\ 40: The larger one is % d \ n", MAXIMUM (a, B ));
38 # endif
39 return 0;
40
41}



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