/in/foo.c: In function 'bubbleSortString':
/in/foo.c:5:19: warning: implicit declaration of function 'strlen' [-Wimplicit-function-declaration]
    5 |         int len = strlen(str);
      |                   ^~~~~~
/in/foo.c:3:1: note: include '<string.h>' or provide a declaration of 'strlen'
    2 | #include <math.h>
  +++ |+#include <string.h>
    3 | void bubbleSortString (char str[])
/in/foo.c:5:19: warning: incompatible implicit declaration of built-in function 'strlen' [-Wbuiltin-declaration-mismatch]
    5 |         int len = strlen(str);
      |                   ^~~~~~
/in/foo.c:5:19: note: include '<string.h>' or provide a declaration of 'strlen'
/in/foo.c: In function 'main':
/in/foo.c:20:26: error: 'inoutStr' undeclared (first use in this function); did you mean 'inputStr'?
   20 |         bubbleSortString(inoutStr);
      |                          ^~~~~~~~
      |                          inputStr
/in/foo.c:20:26: note: each undeclared identifier is reported only once for each function it appears in