1423. 可获得的最大点数

1423. 可获得的最大点数

• 难度: medium
• 原始链接: https://leetcode.cn/problems/maximum-points-you-can-obtain-from-cards
• 标签: 滑动窗口

解法一: 正向计算

go

func maxScore(cardPoints []int, k int) int {
    left := 0
    sum := 0
    for left < k {
        sum += cardPoints[left]
        left++
    }
    left--
    right := len(cardPoints) - 1
    ans := sum
    for i := 0; i < k; i++ {
        sum -= cardPoints[left]
        sum += cardPoints[right]
        left--
        right--
        ans = max(ans, sum)
    }
    return ans
}

func max(num1, num2 int) int {
    if num1 >= num2 {
        return num1
    }
    return num2
}

解法二: 反向计算

go

func maxScore(cardPoints []int, k int) int {
    allSum := 0
    sum := 0
    n := len(cardPoints)
    m := n - k
    for i := 0; i < m; i++ {
        allSum += cardPoints[i]
        sum += cardPoints[i]
    }
    curMin := sum
    for i := m; i < n; i++ {
        sum += cardPoints[i] - cardPoints[i - m]
        curMin = min(curMin, sum)
        allSum += cardPoints[i]
    }
    return allSum - curMin
}

func min(num1, num2 int) int {
    if num1 <= num2 {
        return num1
    }
    return num2
}