/in/foo.cc: In function 'int main()':
/in/foo.cc:11:16: warning: too many arguments for format [-Wformat-extra-args]
  printf(".2f",f);
                ^
/in/foo.cc:10:6: warning: 'f' is used uninitialized in this function [-Wuninitialized]
  f=(f-32)/9*5;
    ~~^~~~