[Someone]

K&R C had implied type of 'int' for both arguments and return value, and didn't list the types of arguments on the line specifying function name, argument names and return type:

  int foo(x,y)
  {
     return baz(x,y);
  }

  bar(x,y,z)
  short x;
  int z;
  {
     return x+y+z;
  }

  baz(x,y,z)
  {
     return 42;
  }