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Algorithms & Data Structureshard

Decide Target via Subsequence Plus/Multiply Expression

Given an array of positive integers nums and a target T: can you choose a subsequence (keep relative order, at least one element) and insert + or * between consecutive chosen elements — standard precedence, * binds first — so the expression equals T?

canReachTarget([2, 3, 5], 11)  ->  true    // 2*3 + 5
canReachTarget([2, 3, 5], 17)  ->  true    // 2 + 3*5
canReachTarget([2, 3, 5], 13)  ->  false   // no subsequence works

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