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#include <iostream>
#include <vector>

class Solution {
public:
    long long maxScore(std::vector<int>& a, std::vector<int>& b) {
        long long sum[5] = { 0, 
            (long long)0xC000'0000'0000'0001, (long long)0xC000'0000'0000'0001,
            (long long)0xC000'0000'0000'0001, (long long)0xC000'0000'0000'0001
        };
        
        int n = b.size();
        for (int i = 0; i < n; ++i) {
            for (int j = 3; j >=0; --j) {
                sum[j + 1] = std::max(sum[j + 1], sum[j] + (long long)a[j] * b[i]);
            }
        }
        
        return sum[4];
    }
};