/in/foo.c: In function 'main':
/in/foo.c:5:15: warning: spurious trailing '%' in format [-Wformat=]
     scanf("%dd%",&a,&b);
               ^
/in/foo.c:5:11: warning: too many arguments for format [-Wformat-extra-args]
     scanf("%dd%",&a,&b);
           ^~~~~~