最大字段和

给定n个整数（可能为负数组成的序列a[1],a[2],a[3],a[4],,,,,,,,,,a[n],求该序列和的字段和的最大值

#include<iostream>using namespace std;int MaxSubSum(int *a, int left, int right);//分治法求最大子段和int main(){int n, result;cout << "请依次输入序列中元素的个数: " << endl;cin >> n;int *a = new int[n];cout << "请依次输入序列中的各元素值:" << endl;for (int i = 0; i < n; i++)cin >> a[i];result = MaxSubSum(a, 0, n - 1);cout << "最大字段的和为" << result<< endl;return 0;}int MaxSubSum(int  *a, int left, int right){int maxSum = 0;if (left == right)return (a[left]>0 ? a[left] : 0);int middle = (left + right) / 2;int leftSum = MaxSubSum(a, left, middle);int rightSum = MaxSubSum(a, middle + 1, right);int i, lefs = 0, rigs = 0,temSum = 0;for (i = middle; i >= left; --i){temSum += a[i];lefs = (temSum > lefs) ? temSum : lefs;}temSum = 0;for (i = middle + 1; i <= right; ++i){temSum += a[i];rigs = (temSum > rigs) ? temSum : rigs;}maxSum = lefs + rigs;if (leftSum > maxSum)maxSum = leftSum;if (rightSum > maxSum)maxSum = rightSum;return maxSum;}