209 min len sub array

209. 长度最小的子数组

cpp：

class Solution
{
public:
    int minSubArrayLen(int target, vector<int>& nums)
    {
        int slow = 0;
        int sum = 0;
        int results = INT_MAX; //宏
        int length = 0;

        for (int fast = 0; fast < nums.size(); fast++)
        {
            sum += nums[fast];

            while (sum >= target)
            {
                length = fast - slow + 1;
                results = results < length ? results : length; //比较，实时更新长度
                sum -= nums[slow];
                slow++;
            }
        }

        return results == INT_MAX ? 0 : results;
    }
};

go：

func minSubArrayLen(target int, nums []int) int {
    slow, length, sum := 0, 0, 0
    results := len(nums) + 1 // +1 是为了实现不存在子数组时返回 0

    for fast := 0; fast < len(nums); fast++ {
        sum += nums[fast]

        for sum >= target {
            length = fast - slow + 1

            if length <= results {
                results = length
            } 

            sum -= nums[slow]
            slow++
        }
    }

    if results == len(nums) + 1 {
        return 0
    } else {
        return results
    }
}