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Start your free trialRafał Stasiak
3,763 PointsWhy whe need to use "not not found" instead of just "found" (!= -1 / ==1)
Hello team,
Why we need to use "not not found" instead of just "found" (!= -1 / ==1)
for example
misses.indexOf(letter) == 1 || hits.indexOf(letter) == 1 ?
Java logic requires misses.indexOf(letter) != -1 || hits.indexOf(letter) != -1 to work properly but why?
I dont get this double negation
1 Answer
Steven Parker
231,271 PointsThe "not found" value is consistently -1, so it's easy to test for. But a "found" result could be any non-negative value, so it would not help to test for any specific one.
You do, however, have other options besides using the "not equals" operator:
misses.indexOf(letter) > -1 || hits.indexOf(letter) > -1 // or ">= 0"