foo.c: In function ‘mm’:
foo.c:29:9: warning: implicit declaration of function ‘printf’ [-Wimplicit-function-declaration]
   29 |         printf("%d %d \n", middle, max);
      |         ^~~~~~
foo.c:1:1: note: include ‘<stdio.h>’ or provide a declaration of ‘printf’
  +++ |+#include <stdio.h>
    1 | void mm(int a, int b, int c)
foo.c:29:9: warning: incompatible implicit declaration of built-in function ‘printf’ [-Wbuiltin-declaration-mismatch]
   29 |         printf("%d %d \n", middle, max);
      |         ^~~~~~
foo.c:29:9: note: include ‘<stdio.h>’ or provide a declaration of ‘printf’
foo.c: In function ‘main’:
foo.c:34:9: warning: implicit declaration of function ‘scanf’ [-Wimplicit-function-declaration]
   34 |         scanf("%d %d %d", &a, &b, &c);
      |         ^~~~~
foo.c:34:9: note: include ‘<stdio.h>’ or provide a declaration of ‘scanf’
foo.c:34:9: warning: incompatible implicit declaration of built-in function ‘scanf’ [-Wbuiltin-declaration-mismatch]
foo.c:34:9: note: include ‘<stdio.h>’ or provide a declaration of ‘scanf’