(1+(4+5+2)-3)Stack= …
hardGrind 75

Basic Calculator

Basic Calculator is about exploring choices without getting lost—choose, recurse, undo, repeat. It's a hard one for a reason: it stresses structured exploration when the rules pile up. The gotcha is duplicates and dead ends—good pruning and ordering rules make this manageable.

StringStackBacktrackingMath & Geometry
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1Basic Calculator Implementationhard
Based onLeetCode

Desktop required

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