题目：
Find the contiguous subarray within an array (containing at least one number) which has the largest sum.
For example, given the array [-2,1,-3,4,-1,2,1,-5,4],
the contiguous subarray [4,-1,2,1] has the largest sum = 6. （Medium）
分析：
遍历一遍，维护一个当前最大值temp，如果temp < 0，则temp = nums[i]（前面的元素和更小，不要加进去）， 否则 temp += nums[i]；
然后每个temp更新result.
代码：
1 class Solution { 2 public: 3 int maxSubArray(vector<int>& nums) { 4 if (nums.size() == 0) { 5 return -1; 6 } 7 int temp = nums[0], result = nums[0]; 8 for (int i = 1; i < nums.size(); ++i) { 9 if (temp < 0) { 10 temp = nums[i]; 11 result = max(temp, result); 12 } 13 else { 14 temp = nums[i] + temp; 15 result = max(temp, result); 16 } 17 } 18 return result; 19 } 20 };
题目还有分治和动归的算法，明天再说...
原文：http://www.cnblogs.com/wangxiaobao/p/5858203.html