Maximize Protected Population with One-Step Left Relocation

You are given n cities arranged from left to right. City i (1-indexed) has population population[i] and a binary string unit of length n where: unit[i] = '1' means city i initially has one security unit, unit[i] = '0' means it has none. You may relocate security units: for any city i > 1 with unit[i] = '1', that unit may optionally move to the immediate left neighbor city i-1. Each unit can be moved at most once (or stay). After relocations, a city is protected if it has at least one security unit. Compute the maximum possible total population of protected cities. Suggested Input Line 1: integer n Line 2: n integers population[1..n] Line 3: binary string unit (length n) Output One integer: the maximum protected population sum Example n = 5, population = [10,5,8,9,6], unit = "01101" → output 27 Constraints (typical) 1 <= n <= 2e5 0 <= population[i] <= 1e9 Example Input 5 10 5 8 9 6 01101 Output 27