RubyInline：错误：函数的参数太少

I have the following C code:

我有以下C代码：

VALUE find_index(VALUE arr, VALUE num_elements, VALUE element){
  ....
}

....

VALUE array_distance(VALUE arr1, VALUE arr2){
  long arr1_len = RARRAY_LEN(arr1);
  VALUE *c_arr2 = RARRAY_PTR(arr2);
  long i;
  for(i = 0; i < arr2_len; i++){
    long arr1_index = find_index(arr1, arr1_len, c_arr2[i]);
    ....
  }
}
VALUE