L53-Maximum-Subarray

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.

解题思路

动态规划思想

以nums数组[-2,1,-3,4,-1]为例

• dp[0]为-2
• dp[1] = max(dp[0]+nums[1],1)=max(-2,1)=1
• dp[2] = max(dp[1]+nums[2],-3)=max(1-3,-3)=-2
• 当前的sum为dp[i-1]+nums[i], nums[i]最大值
• 然后将maxSum和sum进行比较，取最大值

Go代码实现

Go代码实现1

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func (a int, b int)int { if a>b { return a }else{ return b } } func maxSubArray(nums []int) int { n := len(nums) if n == 0 { return 0 } if n == 1 { return nums[0] 大专栏  L53-Maximum-Subarrays="line"> } sums := make([]int, n) maxSum := nums[0] sums[0] = nums[0] for i:=1;i<n ; i++ { sums[i] = max(sums[i-1]+nums[i], nums[i]) maxSum = max(sums[i], maxSum) } return maxSum }

Go代码实现2

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func maxSubArray(nums []int) int { n := len(nums) if n == 0 { return 0 } maxSum := nums[0] curSum := nums[0] for i:=1;i<n ; i++ { if curSum<0 { curSum = nums[i] }else{ curSum += nums[i] } if curSum>maxSum { maxSum = curSum } } return maxSum }

参考文档

• http://blog.csdn.net/liu2012huan/article/details/51296635