/in/foo.cc: In function 'int Is(char*)':
/in/foo.cc:48:1: warning: control reaches end of non-void function [-Wreturn-type]
 }
 ^
/in/foo.cc:32:10: warning: 'k2' may be used uninitialized in this function [-Wmaybe-uninitialized]
  if ((k2 - k1 - 1) % 2 == 0)
       ~~~^~~~
/in/foo.cc:32:10: warning: 'k1' may be used uninitialized in this function [-Wmaybe-uninitialized]