Compilare: user.c: In function 'main': user.c:93: warning: passing argument 1 of 'mul' from incompatible pointer type user.c:94: warning: passing argument 2 of 'mul' from incompatible pointer type user.c:95: warning: passing argument 1 of 'cpy' from incompatible pointer type user.c:100: warning: passing argument 1 of 'sub' from incompatible pointer type user.c:81: warning: unused variable 'fo' user.c:80: warning: unused variable 'fi' user.c:104:2: warning: no newline at end of file