/in/foo.cc: In function 'int main()':
/in/foo.cc:6:23: warning: too many arguments for format [-Wformat-extra-args]
  scanf("%d%d",&a,&b,&d);
                       ^
/in/foo.cc:7:4: error: unable to find numeric literal operator 'operator""d'
  c=5d*a+d;
    ^~
/in/foo.cc:7:4: note: use -std=gnu++11 or -fext-numeric-literals to enable more built-in suffixes