The embedding/encoder may not be working the way you think it is

In issues 33 (https://github.com/carpedm20/ENAS-pytorch/issues/33) I wondered why the Embedding encoder was as large as it was. The response from @carpedm20 was:

> You can assume the same activation in a different place to have the same semantics (embedding) or not. I assumed it's different because activation in different locations may have a separate role.

That makes sense. However, I've been running through this section of the code (Controller.sample()) in the debugger trying to understand what's going on... when `mode` is 0 (the case when activation func is being selected) then `sum(self.num_tokens[:mode])` is 0. So the line:

```
inputs = utils.get_variable(
action[:, 0] + sum(self.num_tokens[:mode]),
requires_grad=False)
```
is always just the action[:,0] component which is a value from 0 to 3 (one of 4 activation functions in the activation function list) since `sum(self.num_tokens[:0]` is 0.

And when mode is 1, the `sum(self.num_tokens[:mode])` is always 4 - so not sure how you can get anything higher than` len(args.shared_rnn_activations)+self.args.num_blocks` here. mode can only take on values of 0 or 1. Either I'm missing something or maybe it's a bug?

with `self.args.num_blocks = 6`, I see `self.num_tokens is: [4, 1, 4, 2, 4, 3, 4, 4, 4, 5, 4, 6, 4]` and `sum(self.num_tokens) = 49`

To actually use all of those 49 entries of the embedding table I suspect that what we need for `inputs` is something along the lines of:

```
inputs = utils.get_variable(
action[:, 0] + sum(self.num_tokens[:block_idx]) ,
requires_grad=False)
```

Start by tracing Controller.sample(), especially the mode, block_idx, num_tokens, and inputs calculation, and inspect how utils.get_variable consumes the selected indices. Compare the computed indices with the embedding table and the activation/block layout; the issue is done when the indexing behavior is confirmed or corrected and the full intended token range is demonstrably handled.

Written by the indexing model from the issue text.