## Go Channel Practice V - 祖安萝莉

Aug 06, 2020 06:17:14 AM

idea 来自 https://www.zhihu.com/question/402635037/answer/1302122540

逻辑没有照抄，只是做 channel 使用方法练习。

## Leetcode - Minimum Increment to Make Array Unique

Jul 15, 2020 06:51:25 AM

https://leetcode.com/problems/minimum-increment-to-make-array-unique/

Given an array of integers A, a *move* consists of choosing any `A[i]`

, and incrementing it by `1`

.

Return the least number of moves to make every value in `A`

unique.

**Example 1:**

Input:[1,2,2]Output:1Explanation:After 1 move, the array could be [1, 2, 3].

**Example 2:**

Input:[3,2,1,2,1,7]Output:6Explanation:After 6 moves, the array could be [3, 4, 1, 2, 5, 7]. It can be shown with 5 or less moves that it is impossible for the array to have all unique values.

## Leetcode - Unique Email Addresses

Jul 15, 2020 02:33:33 AM

https://leetcode.com/problems/unique-email-addresses/

Every email consists of a local name and a domain name, separated by the @ sign.

For example, in `alice@leetcode.com`

, `alice`

is the local name, and `leetcode.com`

is the domain name.

Besides lowercase letters, these emails may contain `'.'`

s or `'+'`

s.

If you add periods (`'.'`

) between some characters in the **local name** part of an email address, mail sent there will be forwarded to the same address without dots in the local name. For example, `"alice.z@leetcode.com"`

and `"alicez@leetcode.com"`

forward to the same email address. (Note that this rule does not apply for domain names.)

If you add a plus (`'+'`

) in the **local name**, everything after the first plus sign will be **ignored**. This allows certain emails to be filtered, for example `m.y+name@email.com`

will be forwarded to `my@email.com`

. (Again, this rule does not apply for domain names.)

It is possible to use both of these rules at the same time.

Given a list of `emails`

, we send one email to each address in the list. How many different addresses actually receive mails?

**Example 1:**

Input:["test.email+alex@leetcode.com","test.e.mail+bob.cathy@leetcode.com","testemail+david@lee.tcode.com"]Output:2Explanation:"testemail@leetcode.com" and "testemail@lee.tcode.com" actually receive mails

## Leetcode - Angle Between Hands of a Clock

Jul 15, 2020 01:29:39 AM

https://leetcode.com/problems/angle-between-hands-of-a-clock/

Given two numbers, `hour`

and `minutes`

. Return the smaller angle (in degrees) formed between the `hour`

and the `minute`

hand.

**Example 1:**

Input:hour = 12, minutes = 30Output:165

## Leetcode - Third Maximum Number

Jul 14, 2020 08:43:09 AM

https://leetcode.com/problems/third-maximum-number/

Given a **non-empty** array of integers, return the **third** maximum number in this array. If it does not exist, return the maximum number. The time complexity must be in O(n).

**Example 1:**

Input:[3, 2, 1]Output:1Explanation:The third maximum is 1.

## Leetcode - Height Checker

Jul 14, 2020 08:20:21 AM

https://leetcode.com/problems/height-checker/

Students are asked to stand in non-decreasing order of heights for an annual photo.

Return the minimum number of students that must move in order for all students to be standing in non-decreasing order of height.

Notice that when a group of students is selected they can reorder in any possible way between themselves and the non selected students remain on their seats.

**Example 1:**

Input:heights = [1,1,4,2,1,3]Output:3Explanation:Current array : [1,1,4,2,1,3] Target array : [1,1,1,2,3,4] On index 2 (0-based) we have 4 vs 1 so we have to move this student. On index 4 (0-based) we have 1 vs 3 so we have to move this student. On index 5 (0-based) we have 3 vs 4 so we have to move this student.

## Leetcode - Sort Array By Parity

Jul 14, 2020 06:06:00 AM

https://leetcode.com/problems/sort-array-by-parity/

Given an array `A`

of non-negative integers, return an array consisting of all the even elements of `A`

, followed by all the odd elements of `A`

.

You may return any answer array that satisfies this condition.

**Example 1:**

Input:[3,1,2,4]Output:[2,4,3,1] The outputs [4,2,3,1], [2,4,1,3], and [4,2,1,3] would also be accepted.

## Leetcode - Duplicate Zeros

Jul 14, 2020 04:23:12 AM

https://leetcode.com/problems/duplicate-zeros/

Given a fixed length array `arr`

of integers, duplicate each occurrence of zero, shifting the remaining elements to the right.

Note that elements beyond the length of the original array are not written.

Do the above modifications to the input array **in place**, do not return anything from your function.

**Example 1:**

Input:[1,0,2,3,0,4,5,0]Output:nullExplanation:After calling your function, theinputarray is modified to: [1,0,0,2,3,0,0,4]

## Leetcode - Sort Transformed Array

Jul 14, 2020 02:19:39 AM

Given a **sorted** array of integers *nums* and integer values *a*, *b* and *c*. Apply a quadratic function of the form f(*x*) = *ax*^{2} + *bx* + *c* to each element *x* in the array.

The returned array must be in **sorted order**.

Expected time complexity: **O( n)**

**Example 1:**

Input:nums = [-4,-2,2,4], a = 1, b = 3, c = 5Output:[3,9,15,33]