Guided tour · Error correction · step 5 of 11
Distance 3 corrects one error, and breaks on two
The relationship between code distance and correctable errors is the most commonly misread number in the field.
First, commit to an answer
A distance-3 code sees two errors instead of one. Does it fail to correct them, or something worse?
Decide before you follow the link. Nothing is recorded — the value is in having been wrong on purpose once.
Now go and look
Apply this weight-2 error and read the verdict and the residual.
What you should see
Something worse. The decoder acts confidently on a syndrome consistent with a single error elsewhere, and its correction is what creates the logical failure — the verdict says miscorrected, not undetected.