53. Maximum Subarray

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.

连续子数组的最大和

C++(9ms):

class Solution {
public:
    int maxSubArray(vector<int>& nums) {
        int len = nums.size() ;
        if (len < 1)
            return 0 ;
        int sum = 0 ;
        int Max = nums[0] ;
        for (int i = 0 ; i < len ; i++){
            if (sum < 0)
                sum = nums[i] ;
            else
                sum += nums[i] ;
            if (sum > Max)
                Max = sum ;
        }
        return Max ;
    }
};

java(15ms):

class Solution {
    public int maxSubArray(int[] nums) {
        if (nums.length < 1)
            return 0 ;
        int Max = nums[0] ;
        int sum = 0 ;
        for(int i = 0 ; i < nums.length ; i++){
            if (sum < 0){
                sum = nums[i] ;
            }else{
                sum += nums[i] ;
            }
            if (sum > Max)
                Max = sum ;
        }
        return Max ;
    }
}