Minimum Absolute Sum

Problem Overview

• Given an integer array A, you may multiply at most one element by -1 to make the total sum as close to zero as possible, returning the minimum absolute sum.
• Constraints: N in [1..100000], elements in [-1000..1000]; output is the minimal absolute value of the sum after the single optional flip.
• Context: Models balancing a net total or minimizing deviation in real-world aggregates.
• From Google interviews; a coding interview problem and common interview question.