# 题目：【二分查找】2024E-孙悟空吃蟠桃
# 分值：200
# 作者：许老师-闭着眼睛学数理化
# 算法：二分查找
# 代码看不懂的地方，请直接在群上提问
# 相关题目：LeetCode875.爱吃香蕉的珂珂


# 导入向上取整函数ceil，用于后续的计算
from math import ceil


nums = list(map(int, input().split()))
h = int(input())


# 计算在速度k的条件下，所花费的时间h的函数
def cal_hour_used(nums, k):
    return sum(ceil(p / k) for p in nums)


# 二分查找求解问题的函数
def minEatingSpeed(nums, h):
    # 左闭右开
    left, right = 1, max(nums) + 1
    while left < right:
        mid = (left + right) // 2
        # 花费时间太少，速度偏大，速度还可以减小，
        # 搜索区间向左折半，right可以向左移动
        if cal_hour_used(nums, mid) <= h:
            right = mid
        else:
            left = mid + 1
    return left


# 如果nums的长度已经大于h，一定无法在h小时内吃完所有蟠桃
# 直接输出0
if len(nums) > h:
    print(0)
# 否则进行二分，输出答案
else:
    print(minEatingSpeed(nums, h))

Java

import java.util.Scanner;

public class Main {

    public static void main(String[] args) {
        Scanner scanner = new Scanner(System.in);
        String[] numsStr = scanner.nextLine().split(" ");
        int[] nums = new int[numsStr.length];
        for (int i = 0; i < numsStr.length; i++) {
            nums[i] = Integer.parseInt(numsStr[i]);
        }
        int h = scanner.nextInt();

        int left = 1;
        int right = getMax(nums) + 1;

        while (left < right) {
            int mid = left + (right - left) / 2;
            if (calHourUsed(nums, mid) <= h) {
                right = mid;
            } else {
                left = mid + 1;
            }
        }

        if (nums.length > h) {
            System.out.println(0);
        } else {
            System.out.println(left);
        }
    }

    public static int calHourUsed(int[] nums, int k) {
        int hour = 0;
        for (int p : nums) {
            hour += Math.ceil((double) p / k);
        }
        return hour;
    }

    public static int getMax(int[] nums) {
        int max = Integer.MIN_VALUE;
        for (int num : nums) {
            max = Math.max(max, num);
        }
        return max;
    }
}

C++

#include <iostream>
#include <vector>
#include <algorithm>
#include <cmath>
#include <climits>
using namespace std;

int calHourUsed(vector<int>& nums, int k) {
    int hour = 0;
    for (int p : nums) {
        hour += ceil((double) p / k);
    }
    return hour;
}

int getMax(vector<int>& nums) {
    int max = INT_MIN;
    for (int num : nums) {
        max = std::max(max, num);
    }
    return max;
}

int main() {
    string input;
    getline(cin, input);
    string input2;
    getline(cin, input2);

    vector<int> nums;
    size_t pos = 0;
    while ((pos = input.find(' ')) != string::npos) {
        nums.push_back(stoi(input.substr(0, pos)));
        input.erase(0, pos + 1);
    }
    nums.push_back(stoi(input));

    int h = stoi(input2);

    int left = 1;
    int right = getMax(nums) + 1;

    while (left < right) {
        int mid = left + (right - left) / 2;
        if (calHourUsed(nums, mid) <= h) {
            right = mid;
        } else {
            left = mid + 1;
        }
    }

    if (nums.size() > h) {
        cout << 0 << endl;
    } else {
        cout << left << endl;
    }

    return 0;
}

时空复杂度

时间复杂度：O(NlogN)。其中N为nums数组长度。
空间复杂度：O(1)。