题目：

题解：

type pair struct{ min, max int }

func maximumGap(nums []int) (ans int) {
    n := len(nums)
    if n < 2 {
        return
    }

    minVal := min(nums...)
    maxVal := max(nums...)
    d := max(1, (maxVal-minVal)/(n-1))
    bucketSize := (maxVal-minVal)/d + 1

    // 存储 (桶内最小值，桶内最大值) 对，(-1, -1) 表示该桶是空的
    buckets := make([]pair, bucketSize)
    for i := range buckets {
        buckets[i] = pair{-1, -1}
    }
    for _, v := range nums {
        bid := (v - minVal) / d
        if buckets[bid].min == -1 {
            buckets[bid].min = v
            buckets[bid].max = v
        } else {
            buckets[bid].min = min(buckets[bid].min, v)
            buckets[bid].max = max(buckets[bid].max, v)
        }
    }

    prev := -1
    for i, b := range buckets {
        if b.min == -1 {
            continue
        }
        if prev != -1 {
            ans = max(ans, b.min-buckets[prev].max)
        }
        prev = i
    }
    return
}

func min(a ...int) int {
    res := a[0]
    for _, v := range a[1:] {
        if v < res {
            res = v
        }
    }
    return res
}

func max(a ...int) int {
    res := a[0]
    for _, v := range a[1:] {
        if v > res {
            res = v
        }
    }
    return res
}