<p>Koko loves to eat bananas. There are <code>n</code> piles of bananas, the <code>i<sup>th</sup></code> pile has <code>piles[i]</code> bananas. The guards have gone and will come back in <code>h</code> hours.</p>

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

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

<p>Return <em>the minimum integer</em> <code>k</code> <em>such that she can eat all the bananas within</em> <code>h</code> <em>hours</em>.</p>

<p>&nbsp;</p>
<p><strong class="example">Example 1:</strong></p>

<pre>
<strong>Input:</strong> piles = [3,6,7,11], h = 8
<strong>Output:</strong> 4
</pre>

<p><strong class="example">Example 2:</strong></p>

<pre>
<strong>Input:</strong> piles = [30,11,23,4,20], h = 5
<strong>Output:</strong> 30
</pre>

<p><strong class="example">Example 3:</strong></p>

<pre>
<strong>Input:</strong> piles = [30,11,23,4,20], h = 6
<strong>Output:</strong> 23
</pre>

<p>&nbsp;</p>
<p><strong>Constraints:</strong></p>

<ul>
	<li><code>1 &lt;= piles.length &lt;= 10<sup>4</sup></code></li>
	<li><code>piles.length &lt;= h &lt;= 10<sup>9</sup></code></li>
	<li><code>1 &lt;= piles[i] &lt;= 10<sup>9</sup></code></li>
</ul>

class Solution {
public:
    bool solve(long long int k, vector<int>& b, long long int h) {
        long long int sum = 0;
        for (int i = 0; i < b.size(); i++) {
            if (b[i] % k == 0) {
                sum += b[i] / k;
            } else {
                sum += (b[i] / k) + 1;
            }
        }
        return sum <= h;
    }
    int minEatingSpeed(vector<int>& b, int h) {
        long long int tr = 0;
        int n = b.size();
        for (int i = 0; i < n; i++) {
            tr = max(tr, (long long int)b[i]);
        }

        long long int low = 1, high = tr, u = 1, answer = -1;
        while (low <= high && u == 1) {
            long long int mid = (low + high) / 2;
            if (solve(mid, b, h) == false) {
                low = mid + 1;
            } else {
                if (mid == 1) {
                    answer = 1;
                    u = 0;
                } else if (solve(mid - 1, b, h) == false) {
                    answer = mid;
                    u = 0;
                } else {
                    high = mid - 1;
                }
            }
        }
        return answer;
    }
};
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