prog.c: In function 'main':
prog.c:5:9: warning: implicit declaration of function 'fib' [-Wimplicit-function-declaration]
return fib(n) % m;
^
prog.c:5:13: error: 'n' undeclared (first use in this function)
return fib(n) % m;
^
prog.c:5:13: note: each undeclared identifier is reported only once for each function it appears in
prog.c:5:18: error: 'm' undeclared (first use in this function)
return fib(n) % m;
^