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An add-on you could use as well as playing Halmic is part of the "Aardvark" system. This uses bids of 2♠ and 2NT to show 5-5 shaped hands (other variations can also be used if you wish to look them up on the Internet).
With a 5-5 shape including spades, you can bid 2♠. Partner leaves this in with 3(+) spades and bids 3♣ with only 2S as a pass or correct bid.
A 2NT bid shows two 5-card suits that do not include spades. Partner bids his longest (3+ cards) minor and responder will either pass or convert to Hearts if he does not have the suit opener has bid.
So summarising, after a double of 1NT :