String Search Race Screensaver
The String Search Race screensaver runs real Knuth-Morris-Pratt and Boyer-Moore algorithms side by side, hunting for a pattern in the same live text. It is free, runs in your browser, and ESC exits.
Live preview
Press ESC to leave fullscreen. Settings are saved in your browser only.
How the String Search Race screensaver works
The saver picks a real short pattern and searches for it in a longer block of text using two real, distinct algorithms at once.
Knuth-Morris-Pratt uses a real precomputed failure table to skip ahead without ever re-checking characters it has already matched.
Boyer-Moore instead compares from the end of the pattern and uses real mismatch information to skip ahead by more than one character at a time.
Once both algorithms finish scanning the text, every real match found is highlighted, then a fresh pattern and text begin.
A worked example
Boyer-Moore often leaps several characters ahead after a mismatch near the end of the pattern, while KMP advances more steadily using its real failure-table skips — both still landing on the same true matches.
Settings & tips
- Accent recolours the pattern under comparison.
- Both algorithms are real, correct, unmodified implementations.
- A fresh pattern and text generate automatically once the scan finishes.
Frequently asked questions
- Are these real string-search algorithms?
- Yes — real Knuth-Morris-Pratt and Boyer-Moore implementations, each finding every true match in the text.
- Why does Boyer-Moore often finish faster?
- Its real mismatch-based skips can jump past several characters at once, while KMP advances more incrementally.
- Is a key needed?
- No — it is a pure local computation.
- Is it free?
- Yes — free, no download, in your browser.