Note 5 - Stockholders' Equity - Warrant Activity (Details) - Common Stock Warrants [Member] - $ / shares |
3 Months Ended | |
|---|---|---|
Jul. 31, 2026 |
Apr. 30, 2026 |
|
| Warrants, outstanding (in shares) | 2,102,547 | |
| Warrants, outstanding, weighted average strike price (in dollars per share) | $ 9.59 | $ 9.59 |
| Warrants, issued (in shares) | 0 | |
| Warrants, cancelled (in shares) | 0 | |
| Warrants, forfeited (in shares) | 0 | |
| Warrants, outstanding (in shares) | 2,102,547 | |
| Minimum [Member] | ||
| Warrants, outstanding, exercise price (in dollars per share) | $ 0.001 | 0.001 |
| Maximum [Member] | ||
| Warrants, outstanding, exercise price (in dollars per share) | $ 425 | $ 425 |