/in/foo.c: In function 'fun':
/in/foo.c:15:8: warning: implicit declaration of function 'abs' [-Wimplicit-function-declaration]
   n3 = abs(n1-n2);
        ^~~
/in/foo.c:24:9: warning: 'count' may be used uninitialized in this function [-Wmaybe-uninitialized]
    count++;
    ~~~~~^~