题目：

题解：

func checkSubarraySum(nums []int, k int) bool {
    m := len(nums)
    if m < 2 {
        return false
    }
    mp := map[int]int{0: -1}
    remainder := 0
    for i, num := range nums {
        remainder = (remainder + num) % k
        if prevIndex, has := mp[remainder]; has {
            if i-prevIndex >= 2 {
                return true
            }
        } else {
            mp[remainder] = i
        }
    }
    return false
}