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.
解决方法: 动态规划
状态方程: f[n] = max(f[n - 1] + nums[i], nums[i])
f[n] 表示以第i个字符为结尾的最大子字符串和
public class Solution { public int maxSubArray(int[] nums) { if(nums == null || nums.length == 0) { return Integer.MIN_VALUE; } int length = nums.length; int[] f = new int[length]; f[0] = nums[0]; int max = nums[0]; for(int i = 1; i < length; i++) { if(f[i - 1] + nums[i] > nums[i]) { f[i] = f[i - 1] + nums[i]; } else { f[i] = nums[i]; } max = Math.max(max,f[i]); } return max; } }