[LeetCode 题解]: Maximum Subarray

前言

【LeetCode 题解】系列传送门：  http://www.cnblogs.com/double-win/category/573499.html

1.题目描述

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.

More practice:

If you have figured out the O(n) solution, try coding another solution using the divide and conquer approach, which is more subtle.

2. 解法

class Solution {
public:
    int maxSubArray(int A[], int n) {
        int sum,ans,i,mark=0;
        sum=ans=i=0;
        
        for(i=0;i<n;i++)
           if(A[i]>=0) mark=1;
        
        if(mark==0)
        {
            ans=A[0];
            for(i=1;i<n;i++)
               if(A[i]>ans) ans=A[i];
            
        }
        else
        {
            for(i=0;i<n;i++)
            {
               sum+=A[i];
               if(sum<0)
                   sum=0;
               if(sum>ans) ans=sum;
            }
        }
        return ans;        
    }
};

3. 相关题目

Gas Station 题解 http://www.cnblogs.com/double-win/p/3746637.html

作者：Double_Win 出处:   http://www.cnblogs.com/double-win/p/3746672.html 声明： 由于本人水平有限，文章在表述和代码方面如有不妥之处，欢迎批评指正~