A step forward every day

You have an array a consisting of n integers. Each integer from 1 to n appears exactly once in this array.

For some indices i (1 ≤ i ≤ n - 1) it is possible to swap i-th element with (i + 1)-th, for other indices it is not possible. You may perform any number of swapping operations any order. There is no limit on the number of times you swap i-th element with (i + 1)-th (if the position is not forbidden).

Can you make this array sorted in ascending order performing some sequence of swapping operations?

虽然在Windows上Chrome浏览器占据着霸主地位，但是在Linux上，明显面向开源社区的Firefox对各种发行版例如Ubuntu等优化得更棒。虽然Html5是趋势，但是Flash在日常浏览网页中依旧不能少。Ubuntu中的Firefox没有像Chrome一样内置Pepper Flash插件，而Adobe早已对Ubuntu停更。那么要如何为Ubuntu下的Firefox安装最新的Flash插件呢？

It is winter now, and Max decided it’s about time he watered the garden.

The garden can be represented as n consecutive garden beds, numbered from 1 to n. k beds contain water taps (i-th tap is located in the bed x**i), which, if turned on, start delivering water to neighbouring beds. If the tap on the bed x**i is turned on, then after one second has passed, the bed x**i will be watered; after two seconds have passed, the beds from the segment [x**i - 1, x**i + 1] will be watered (if they exist); after j seconds have passed (j is an integer number), the beds from the segment [x**i - (j - 1), x**i + (j - 1)] will be watered (if they exist). Nothing changes during the seconds, so, for example, we can’t say that the segment [x**i - 2.5, x**i + 2.5] will be watered after 2.5seconds have passed; only the segment [x**i - 2, x**i + 2] will be watered at that moment.

The garden from test 1. White colour denotes a garden bed without a tap, red colour — a garden bed with a tap.

The garden from test 1 after 2 seconds have passed after turning on the tap. White colour denotes an unwatered garden bed, blue colour — a watered bed.

Max wants to turn on all the water taps at the same moment, and now he wonders, what is the minimum number of seconds that have to pass after he turns on some taps until the whole garden is watered. Help him to find the answer!

Recently n students from city S moved to city P to attend a programming camp.

They moved there by train. In the evening, all students in the train decided that they want to drink some tea. Of course, no two people can use the same teapot simultaneously, so the students had to form a queue to get their tea.

i-th student comes to the end of the queue at the beginning of l**i-th second. If there are multiple students coming to the queue in the same moment, then the student with greater index comes after the student with lesser index. Students in the queue behave as follows: if there is nobody in the queue before the student, then he uses the teapot for exactly one second and leaves the queue with his tea; otherwise the student waits for the people before him to get their tea. If at the beginning of r**i-th second student i still cannot get his tea (there is someone before him in the queue), then he leaves the queue without getting any tea.

For each student determine the second he will use the teapot and get his tea (if he actually gets it).

You are given a string, s, and a list of words, words, that are all of the same length. Find all starting indices of substring(s) in s that is a concatenation of each word in words exactly once and without any intervening characters.

For example, given:
s: "barfoothefoobarman"
words: ["foo", "bar"]

You should return the indices: [0,9].
(order does not matter).

介绍git的结构、作用以及基本常用命令

Markdown 是一种轻量级标记语言，创始人为约翰·格鲁伯（英语：John Gruber）。它允许人们“使用易读易写的纯文本格式编写文档，然后转换成有效的XHTML(或者HTML)文档”。[4]这种语言吸收了很多在电子邮件中已有的纯文本标记的特性。

Luba is surfing the Internet. She currently has n opened tabs in her browser, indexed from 1 to n from left to right. The mouse cursor is currently located at the pos-th tab. Luba needs to use the tabs with indices from l to r (inclusive) for her studies, and she wants to close all the tabs that don’t belong to this segment as fast as possible.

Each second Luba can either try moving the cursor to the left or to the right (if the cursor is currently at the tab i, then she can move it to the tab max(i - 1, a) or to the tab min(i + 1, b)) or try closing all the tabs to the left or to the right of the cursor (if the cursor is currently at the tab i, she can close all the tabs with indices from segment [a, i - 1] or from segment [i + 1, b]). In the aforementioned expressions a and b denote the minimum and maximum index of an unclosed tab, respectively. For example, if there were 7 tabs initially and tabs 1, 2and 7 are closed, then a = 3, b = 6.

What is the minimum number of seconds Luba has to spend in order to leave only the tabs with initial indices from l to r inclusiveopened?

You are given two positive integer numbers a and b. Permute (change order) of the digits of a to construct maximal number not exceeding b. No number in input and/or output can start with the digit 0.

It is allowed to leave a as it is.

Luba thinks about watering her garden. The garden can be represented as a segment of length k. Luba has got n buckets, the i-th bucket allows her to water some continuous subsegment of garden of length exactly a**i each hour. Luba can’t water any parts of the garden that were already watered, also she can’t water the ground outside the garden.

Luba has to choose one of the buckets in order to water the garden as fast as possible (as mentioned above, each hour she will water some continuous subsegment of length a**i if she chooses the i-th bucket). Help her to determine the minimum number of hours she has to spend watering the garden. It is guaranteed that Luba can always choose a bucket so it is possible water the garden.

See the examples for better understanding.