Given a sorted array of integers and an integer called target, return the index of the target. If target doesn't exist then return -1.
Solve this in O(logn) time complexity.
 Example 1:
<pre style="white-space: pre-wrap; word-break: keep-all;">Input: <code>nums</code> = [-1,0,3,5,9,12], <code>target</code> = 9 Output: 4 Explanation: Return index 4 because 9 is there.</pre>
Example 2:
<pre style="white-space: pre-wrap; word-break: keep-all;">Input: <code>nums</code> = [-1,0,3,5,9,12], <code>target</code> = 2 Output: -1 Explanation: Return -1 because 2 doesn't exist</pre>
&nbsp;

Binary Search

You are given an array of integers, nums. Return an array of the same length, in which the ith element represents the count of smaller elements to the right of <code>nums[i]</code>. 

Example:

<pre style="white-space: pre-wrap; word-break: keep-all;">
Input: [5,3,4,7,2]
Output: <code>[3,1,1,1,0] 
Explanation:</code>
There are 3 smaller elements (3, 4, 2) on the right side of 5.
There is only 1 smaller element (2) on the right side of 3.
There is 1 smaller element (2) on the right side of 4.
There is 1 smaller element (2) on the right side of 7.
There is 0 smaller element on the right side of 2.
</pre>

Count Smaller Numbers

Given two integers: a dividend and divisor, return the quotient of the two integers. You cannot use multiplication, division and the mod operator.
The integer division should round toward zero.
Example 1:
<pre style="white-space: pre-wrap; word-break: keep-all;">Input: dividend = 11, divisor = 3
Output: 3</pre>
Example 2:
<pre style="white-space: pre-wrap; word-break: keep-all;">Input: dividend = 8, divisor = -3
Output: -2</pre>
Note:
<ul>
<li>The input values will be 32-bit signed integers.</li>
<li>You can assume the divisor will never be 0.</li>
<li>If the division result overflows return&nbsp;231 &minus; 1.</li>
</ul>

Integer Division

You have an array sorted in ascending order but it is rotated at a certain pivot point that is unknown to you. Return the minimum element in the array. No duplicates exist in the array.
(i.e., &nbsp;<code>[0,1,2,4,5,6,7]</code>&nbsp;becomes&nbsp;&nbsp;<code>[4,5,6,7,0,1,2]</code>).
Example 1:
<pre style="white-space: pre-wrap; word-break: keep-all;">Input: [3,4,5,1,2] 
Output: 1
</pre>
Example 2:
<pre style="white-space: pre-wrap; word-break: keep-all;">Input: [4,5,6,7,0,1,2]
Output: 0
</pre>

Identify Smallest In Modified Sorted Array

You are given an array of integers and are asked to find and return the duplicate number in the array. Only one number is repeated in the array.
Note:
Your solution must have a complexity that's less than O(n2). Your solution's space complexity should be constant O(1). You are not allowed to modify the input array. Only one value is repeated in the input array but it can be repeated multiple times.
Example 1:
<pre style="white-space: pre-wrap; word-break: keep-all;">Input: <code>[1,3,4,2,2]</code> Output: 2</pre>
Example 2:
<pre style="white-space: pre-wrap; word-break: keep-all;">Input: [3,1,3,4,2]
Output: 3</pre>
&nbsp;

Identify Repeated Number

Given two integer arrays, return the intersection of the two arrays.
Example 1:
<pre style="white-space: pre-wrap; word-break: keep-all;">Input: nums1 = [1,2,2,1], nums2 = [2,2]
Output: [2]
</pre>
<div>
Example 2:
<pre style="white-space: pre-wrap; word-break: keep-all;">Input: nums1 = [4,9,5], nums2 = [9,4,9,8,4]
Output: [9,4]</pre>
</div>
&nbsp;

Intersection Of Two Arrays

Koko loves eating bananas.&nbsp; You are given an array <code>piles</code>, where <code>piles[i]</code> represents the number of bananas in each position, <code>i</code>.

Koko is trying to finish eating all the bananas in the <code>piles</code> before the guards come back in <code>H</code> hours.

Let <code>K</code> represent the number of bananas she can eat in one hour. Determine minimum integer <code>K</code> such that she can eat all the bananas within <code>H</code> hours.

If a pile has less than <code>K</code> bananas, she eats all of them in that position but doesn't eat anymore in other piles during that hour.

&nbsp;

<ul>
</ul>

<div>
Example 1:

<pre style="white-space: pre-wrap; word-break: keep-all;">
Input: piles = [3,6,7,11], H = 8
Output: 4
</pre>

<div>
Example 2:

<pre style="white-space: pre-wrap; word-break: keep-all;">
Input: piles = [30,11,23,4,20], H = 5
Output: 30
</pre>

<div>
Example 3:

<pre style="white-space: pre-wrap; word-break: keep-all;">
Input: piles = [30,11,23,4,20], H = 6
Output: 23
</pre>

&nbsp;

Note:

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

Monkey Eats Banana

Suppose a sorted array of integers in ascending order is rotated at a pivot index and now you're given this array and a target value. Return the index where the target value is at if it doesn't exist return -1.
(i.e., <code>[0,1,2,4,5,6,7]</code> rotates and becomes&nbsp;<code>[4,5,6,7,0,1,2]</code>).
Assume no duplicates exist.
The solution must run in&nbsp;O(log&nbsp;n).
Example 1:
<pre style="white-space: pre-wrap; word-break: keep-all;">Input: nums = [<code>4,5,6,7,0,1,2]</code>, target = 0 Output: 4</pre>
Example 2:
<pre style="white-space: pre-wrap; word-break: keep-all;">Input: nums = [<code>4,5,6,7,0,1,2]</code>, target = 3 Output: -1</pre>

Search Rotated Array

Given a sorted array of integers in ascending order and a target value, return the index of the target. If the target doesn't exist, return the index where the target can be inserted such that the array is still in sorted order.
Assume no duplicates in the given array.
Example 1:
<pre style="white-space: pre-wrap; word-break: keep-all;">Input: [1,3,5,6], 5
Output: 2
</pre>
Example 2:
<pre style="white-space: pre-wrap; word-break: keep-all;">Input: [1,3,5,6], 2
Output: 1
</pre>
Example 3:
<pre style="white-space: pre-wrap; word-break: keep-all;">Input: [1,3,5,6], 7
Output: 4
</pre>
Example 4:
<pre style="white-space: pre-wrap; word-break: keep-all;">Input: [1,3,5,6], 0
Output: 0
</pre>

Find Insert Index

Given an integer, x, return the square root of x rounded down to the nearest integer.
Example 1:
<pre style="white-space: pre-wrap; word-break: keep-all;">Input: 4
Output: 2
</pre>
Example 2:
<pre style="white-space: pre-wrap; word-break: keep-all;">Input: 8
Output: 2
Explanation: The square root of 8 is 2.82842 so round down to 2 and return it.
</pre>

Square Root

You are given an integer k which represents K number of eggs and an integer N which represents the number of floors in a building.
You want to find out the highest floor such that an egg won't break at that floor. For each move, you are allowed to drop an egg from any floor between 1 to N, if an egg breaks then you cannot drop it anymore.&nbsp;
Return the minimum number of moves to determine the highest floor such that an egg dropped will not break.
<div>
Example 1:
<pre style="white-space: pre-wrap; word-break: keep-all;">Input: K = 1, N = 2
Output: 2
Explanation: 
Drop the egg from floor 1. If it breaks, we know with certainty that the first floor will break the egg.
If it doesn't break, drop the egg from floor 2. If it breaks, we know with certainty that the seccond floor will break the egg.
If it didn't break, then we know that the second floor won't break the egg.
So we return 2 because in the worst case we need 2 moves to find out the max height an egg can be dropped from without breaking.
</pre>
<div>
Example 2:
<pre style="white-space: pre-wrap; word-break: keep-all;">Input: K = 2, N = 6
Output: 3
</pre>
<div>
Example 3:
<pre style="white-space: pre-wrap; word-break: keep-all;">Input: K = 3, N = 14
Output: 4
</pre>
</div>
</div>
</div>

Problem Title	Difficulty	Frequency in Interviews
Search Rotated Array	Medium
Intersection Of Two Arrays	Easy
Identify Repeated Number	Medium
Count Smaller Numbers	Hard
Square Root	Easy
Integer Division	Medium
Identify Smallest In Modified Sorted Array	Medium
Dropping Eggs	Hard
Find Insert Index	Easy
Binary Search	Easy
Monkey Eats Banana	Medium

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