lavos/cap3/ex27.go

package cap3

type Ex27Condition int

const (
    Ex27ConditionMin Ex27Condition = iota
    Ex27ConditionMax
)

func Ex27(nums []int) (max1, max2, min1, min2 int) {
    size := len(nums)
    if size < 3 {
        return
    }

    // 最大的乘积
    maxProd := nums[size-1] * nums[1]
    max1, max2 = nums[size-1], nums[1]

    // 最小的乘积
    minProd := nums[size-1] * nums[1]
    min1, min2 = nums[size-1], nums[1]

    for i := 1; i < size; i++ {
        first, second := (size+i-1)%size, (i+1)%size
        // 当前的乘积
        currentProd := nums[first] * nums[second]

        // 找出最大最小的乘积
        if currentProd > maxProd {
            maxProd = currentProd
            max1, max2 = nums[first], nums[second]
        } else if currentProd < minProd {
            minProd = currentProd
            min1, min2 = nums[first], nums[second]
        }
    }

    return max1, max2, min1, min2
}