三个月算法进阶--day17

class Solution:
    def maxSubArray(self, nums: List[int]) -> int:
        ans = nums[0]
        res = ans
        for i in range(1, len(nums)):
            if ans <= 0:
                ans = nums[i]
            else:
                ans += nums[i]
            res = max(ans, res)
        return res

class Solution:
    def maxSubArray(self, nums: List[int]) -> int:
        res = nums[0]
        for i in range(1, len(nums)):
            nums[i] = max(nums[i-1] + nums[i], nums[i])
            res = max(nums[i], res)
        return res

function Status(l, r, m, i) {
    this.lSum = l;
    this.rSum = r;
    this.mSum = m;
    this.iSum = i;
}

const pushUp = (l, r) => {
    const iSum = l.iSum + r.iSum;
    const lSum = Math.max(l.lSum, l.iSum + r.lSum);
    const rSum = Math.max(r.rSum, r.iSum + l.rSum);
    const mSum = Math.max(Math.max(l.mSum, r.mSum), l.rSum + r.lSum);
    return new Status(lSum, rSum, mSum, iSum);
}

const getInfo = (a, l, r) => {
    if (l === r) return new Status(a[l], a[l], a[l], a[l]);
    const m = (l + r) >> 1;
    const lSub = getInfo(a, l, m);
    const rSub = getInfo(a, m + 1, r);
    return pushUp(lSub, rSub);
}

var maxSubArray = function(nums) {
    return getInfo(nums, 0, nums.length - 1).mSum;
};