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Day 12MediumSmart Interviews
Ternary Array Cost
Local Cost Minimization / GreedySolved Nov 9, 2025
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ProblemProblem statementGiven an array A (elements can be anything), convert it to a ternary array B (elements must be 0, 1, or 2). The cost is sum |A[i] - B[i]|. Crucially, the constraint is that A[i] ≠ B[i]. Find the minimum total conversion cost.ReadHide
Problem Description
Given an array A (elements can be anything), convert it to a ternary array B (elements must be 0, 1, or 2). The cost is sum |A[i] - B[i]|. Crucially, the constraint is that A[i] ≠ B[i]. Find the minimum total conversion cost.