off-by-one error(redirected from Fencepost problem)
Also found in: Idioms.
An exceedingly common error induced in many ways, such as by starting at zero when you should have started at one or vice-versa, or by writing "< N" instead of "<= N" or vice-versa. Often confounded with fencepost error, which is properly a particular subtype of it.
This article is provided by FOLDOC - Free Online Dictionary of Computing (foldoc.org)