---
tags: leetcode
---

# [875. Koko Eating Bananas](https://leetcode.com/problems/koko-eating-bananas/)
---
# My Solution
## The Key Idea for Solving This Coding Question
## C++ Code

class Solution {
public:
    int minEatingSpeed(vector<int> &piles, int h) {
        int left = 1, right = 1000000000;
        while (left < right) {
            int middle = left + (right - left) / 2;
            if (isPossible(piles, middle , h)) {
                // Koko eats too fast.
                right = middle;
            } else {
                left = middle + 1;
            }
        }

        return left;
    }

private:
    bool isPossible(vector<int> &piles, int k, int h) {
        int time = 0;
        for (auto &bananas : piles) {
            time = time + bananas / k;
            if (bananas % k) {
                ++time;
            }
        }
        return time <= h;
    }
};

## Time Complexity
$O(n \cdot \log m)$
$n$ is the length of `piles`.
$m$ is the maximum number of bananas in a singile pile from `piles`.
## Space Complexity
$O(1)$
# Miscellane
<!--
# Test Cases

[3,6,7,11]
8

[30,11,23,4,20]
5

[30,11,23,4,20]
6

* Runtime Error

[312884470]
968709470

* Wrong Answer
https://leetcode.com/problems/koko-eating-bananas/submissions/866697367/
-->