​2021-03-23：给定一个正整数组成的无序数组arr，给定一个正整数值K

package main

import "fmt"

func main() {
    arr := []int{1, 2, 3, 0}
    ret := getMaxLength(arr, 6)
    fmt.Println(ret)
}
func getMaxLength(arr []int, K int) int {
    arrLen := len(arr)
    if arrLen == 0 {
        return 0
    }
    ans := 0
    left := 0
    right := 0

    sum := arr[0]
    for right < arrLen-1 {
        if sum == K {
            ans = getMax(ans, right-left+1)
            right++
            sum += arr[right]
        } else if sum < K {
            right++
            sum += arr[right]
        } else {
            sum -= arr[left]
            left++
        }
    }

    if sum == K {
        ans = getMax(ans, right-left+1)
    }

    return ans
}

func getMax(a int, b int) int {
    if a > b {
        return a
    } else {
        return b
    }
}