/in/foo.cc: In function 'int main()':
/in/foo.cc:6:18: warning: 'I' flag used with '%f' gnu_scanf format [-Wformat=]
    6 |         scanf("%If",&f);
      |                  ^
/in/foo.cc:6:18: warning: format '%f' expects argument of type 'float*', but argument 2 has type 'double*' [-Wformat=]
    6 |         scanf("%If",&f);
      |                ~~^  ~~
      |                  |  |
      |                  |  double*
      |                  float*
      |                %Ilf