Number of cardiology wards

The chief physician needs a quick summary: how many cardiology wards the hospital has. The codes of these wards start with the CARD prefix. Count the number of distinct wards with this prefix and name the result column wards_count.

Expected output sample

This is what a correct answer looks like — its row count is its own, it doesn't have to match the schema tables.

wards_count
3

Your query result will appear here

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