【題解】LeetCode 918. Maximum Sum Circular Subarray

class Solution {
public:
    int maxSubarraySumCircular(vector<int>& A) {
        int mx = A[0], alltot = 0, tot1 = 0, tot2, mxtot = 0, mntot = 0;
        for (int i = 0; i < A.size(); i++){
            mx = max(mx, A[i]);
            alltot += A[i];
            tot1 += A[i];
            mxtot = max(mxtot, tot1);
            tot2 += A[i];
            mntot = min(mntot, tot2);
            if (tot1 < 0) tot1 = 0;
            if (tot2 > 0) tot2 = 0;
        }
        mxtot = max(mxtot, alltot - mntot);
        if (mx < 0) return mx;
        else return mxtot;
    }
};