Note 4 - Stock-based Compensation	3 Months Ended
Jul. 27, 2019
Notes to Financial Statements
Share-based Payment Arrangement [Text Block]	4. STOCK-BASED COMPENSATION During the three months ended July 27, 2019, options to purchase 400 shares were exercised (weighted average exercise price of $17.59 per share). At July 27, 2019, options to purchase 322,045 shares (weighted average exercise price of $11.13 per share) were outstanding and stock-based awards to purchase 2,811,613 shares of common stock were available for grant.

The entire disclosure for share-based payment arrangement.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-URI http://asc.fasb.org/topic&trid=2228938

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