# Leetcode 875. Koko Eating Bananas

1 min readJan 21, 2022

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[medium]

Koko loves to eat bananas. There are `n` piles of bananas, the `ith` pile has `piles[i]` bananas. The guards have gone and will come back in `h` hours.

Koko can decide her bananas-per-hour eating speed of `k`. Each hour, she chooses some pile of bananas and eats `k` bananas from that pile. If the pile has less than `k` bananas, she eats all of them instead and will not eat any more bananas during this hour.

Koko likes to eat slowly but still wants to finish eating all the bananas before the guards return.

Return the minimum integer `k` such that she can eat all the bananas within `h` hours.

Example 1:

`Input: piles = [3,6,7,11], h = 8Output: 4`

Example 2:

`Input: piles = [30,11,23,4,20], h = 5Output: 30`

Example 3:

`Input: piles = [30,11,23,4,20], h = 6Output: 23`

Constraints:

• `1 <= piles.length <= 104`
• `piles.length <= h <= 109`
• `1 <= piles[i] <= 109`

[Think]

1. find the max pile and do the binary search
2. if monkey could eat all the banana, move the start to become mid+1; otherwise move end to become mid-1
3. start the begin point on 1 instead of 0, because at least need 1 hour to finish the pile

[Java]