题目链接 题意 给出一个长度为\(n\)的序列\(a\),问有多少个区间\([l,r]\)满足:在区间\([l,r]\)内,\([1,r-l+1]\)的每个整数都恰好出现了一次. \(n \le 3 \times 10 ^ 5\),\(a_i \le n\) 思路 可以发现,其实最后的答案一定不会很大. 所以:暴力出奇迹!!! 先对题意进行小小的转化,题目等价于问有多少个区间\([l,r]\)满足以下两个条件: 1.区间\([l,r]\)中的每个数字都只在区间\([l,r]\)中出现了一遍 2.…

做法①:RMQ(预处理NLOGN+后续跳跃蜜汁复杂度) 满足题意的区间的条件转换: 1.长度为R-L+1则最大值也为R-L+1 2.区间内的数不重复 当RMQ(L,R)!=R-L+1时 因为已经保证了 i~r[i] 之间的数不重复 则RMQ(L,R)必定大于当前的R-L+1 所以我们需要至少跳到 i+RMQ(L,R)-1 #include<bits/stdc++.h> using namespace std; ], r[]; ]; ][]; int n,ans; void rmqinit()…

题意: 求区间[l, r]是一个1~r-l+1的排列的区间个数 n<=3e5 思路: 如果[l,r]是一个排列,首先这里面的数应该各不相同,然后max(l,r)应该等于r-l+1,这就能唯一确定这个区间满足条件了 我们只需要预处理出对于每个左端点,它能伸延到的最远的r,使得l到r各不相同,然后暴力 注意如果对于一次暴力不满足max(l,r)==r-l+1,那么此时r应该跳到l+max(r-l+1)-1,因为在这里才至少可能会满足条件 代码: #include<iostream> #inc…

Codeforces 题面传送门 & 洛谷题面传送门 由于这场的 G 是道毒瘤题,蒟蒻切不动就只好来把这场的 F 水掉了 看到这样的设问没人想到这道题吗?那我就来发篇线段树+单调栈的做法. 首先显然一个区间 \([l,r]\) 满足条件当且仅当: \([l,r]\) 中不存在重复的数值 \([l,r]\) 中最小值为 \(1\) \([l,r]\)​ 中最大值与最小值的差为 \(r-l\)​ 题解区中某位大佬说过:"数区间的题无非两种套路,枚举端点和分治",这里咱们考虑枚举端点…

目录 1. Math 对象:数学对象,提供对数据的数学计算.如:获取绝对值.向上取整等.无构造函数,无法被初始化,只提供静态属性和方法. 2. Number 对象 :Js中提供数字的对象.包含整数.浮点数等等.并提供数字的类型转换.小数点截取等方法. 1. Math 对象 1.1 介绍 Math 对象,是数学对象,提供对数据的数学计算,如:获取绝对值.向上取整等.无构造函数,无法被初始化,只提供静态属性和方法. 1.2 构造函数 无 :Math 对象无构造函数,无法被初始化,只提供静态属性和方法…

题意:求f(n)=1/1+1/2+1/3+1/4-1/n   (1 ≤ n ≤ 108).,精确到10-8    (原题在文末) 知识点:      调和级数(即f(n))至今没有一个完全正确的公式,但欧拉给出过一个近似公式:(n很大时)       f(n)≈ln(n)+C+1/2*n       欧拉常数值:C≈0.57721566490153286060651209       c++ math库中,log即为ln. 题解: 公式:f(n)=ln(n)+C+1/(2*n); n很小时直接求…

Given a list of non negative integers, arrange them such that they form the largest number. For example, given [3, 30, 34, 5, 9], the largest formed number is 9534330. Note: The result may be very large, so you need to return a string instead of an i…

Eclipse 无法找到 该 断点,原因是编译时,字节码改变了,导致eclipse无法读取对应的行了 1.ANT编译的class Eclipse不认,因为eclipse也会编译class.怎么让它们统一呢,就是在build.xml里的javac标签里加上一句debug="true",一切就OK了. 如:<javac ... debug="true"> 链接:http://blog.csdn.net/liu251/article/details/36391…

/*移除HTML5 input在type="number"时的上下小箭头*/ input::-webkit-outer-spin-button, input::-webkit-inner-spin-button{ -webkit-appearance: none; margin:; } input[type="number"]{-moz-appearance:textfield;}…

真机调试免费App ID出现的问题The maximum number of apps for free development profiles has been reached.免费应用程序调试最大限度苹果免费App ID只能运行2个应用程序,当调试第三个的时候就会报这个错误,必须把之前的应用程序删除,才能调试新的 解决办法:1.连接iPhone 打开Xcode->Window->Devices     2.接着出现这个界面   3.删除其中一个,不是本次运行的应用程序 4.接着会弹框  …

每一个实数都能用有理数去逼近到任意精确的程度,这就是有理数的稠密性.The rational points are dense on the number axis.…

There are a number of spherical balloons spread in two-dimensional space. For each balloon, provided input is the start and end coordinates of the horizontal diameter. Since it's horizontal, y-coordinates don't matter and hence the x-coordinates of s…

Given n points in the plane that are all pairwise distinct, a "boomerang" is a tuple of points (i, j, k) such that the distance between i and j equals the distance between i and k (the order of the tuple matters). Find the number of boomerangs.…

Count the number of segments in a string, where a segment is defined to be a contiguous sequence of non-space characters. Please note that the string does not contain any non-printable characters. Example: Input: "Hello, my name is John" Output:…

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: 1 Explanation: The third maximum is 1. Examp…

Given an integer, write an algorithm to convert it to hexadecimal. For negative integer, two’s complement method is used. Note: All letters in hexadecimal (a-f) must be in lowercase. The hexadecimal string must not contain extra leading 0s. If the nu…

We are playing the Guess Game. The game is as follows: I pick a number from 1 to n. You have to guess which number I picked. Every time you guess wrong, I'll tell you whether the number I picked is higher or lower. However, when you guess a particula…

We are playing the Guess Game. The game is as follows: I pick a number from 1 to n. You have to guess which number I picked. Every time you guess wrong, I'll tell you whether the number is higher or lower. You call a pre-defined API guess(int num) wh…

Given n nodes labeled from 0 to n - 1 and a list of undirected edges (each edge is a pair of nodes), write a function to find the number of connected components in an undirected graph. Example 1: 0          3 |          | 1 --- 2    4 Given n = 5 and…

Given two arrays of length m and n with digits 0-9 representing two numbers. Create the maximum number of length k <= m + n from digits of the two. The relative order of the digits from the same array must be preserved. Return an array of the k digit…

Write a program to find the nth super ugly number. Super ugly numbers are positive numbers whose all prime factors are in the given prime list primes of sizek. For example, [1, 2, 4, 7, 8, 13, 14, 16, 19, 26, 28, 32] is the sequence of the first 12 s…

Additive number is a positive integer whose digits can form additive sequence. A valid additive sequence should contain at least three numbers. Except for the first two numbers, each subsequent number in the sequence must be the sum of the preceding…

A 2d grid map of m rows and n columns is initially filled with water. We may perform an addLand operation which turns the water at position (row, col) into a land. Given a list of positions to operate, count the number of islands after each addLand o…

Given an array nums containing n + 1 integers where each integer is between 1 and n (inclusive), prove that at least one duplicate element must exist. Assume that there is only one duplicate number, find the duplicate one. Note: You must not modify t…

Given an array containing n distinct numbers taken from 0, 1, 2, ..., n, find the one that is missing from the array. For example, Given nums = [0, 1, 3] return 2. Note: Your algorithm should run in linear runtime complexity. Could you implement it u…

Write a program to find the n-th ugly number. Ugly numbers are positive numbers whose prime factors only include 2, 3, 5. For example, 1, 2, 3, 4, 5, 6, 8, 9, 10, 12 is the sequence of the first 10 ugly numbers. Note that 1 is typically treated as an…

Write a program to check whether a given number is an ugly number. Ugly numbers are positive numbers whose prime factors only include 2, 3, 5. For example, 6, 8 are ugly while 14 is not ugly since it includes another prime factor 7. Note that 1 is ty…

Given an array of numbers nums, in which exactly two elements appear only once and all the other elements appear exactly twice. Find the two elements that appear only once. For example: Given nums = [1, 2, 1, 3, 2, 5], return [3, 5]. Note: The order…

A strobogrammatic number is a number that looks the same when rotated 180 degrees (looked at upside down). Write a function to count the total strobogrammatic numbers that exist in the range of low <= num <= high. For example,Given low = "50&qu…

A strobogrammatic number is a number that looks the same when rotated 180 degrees (looked at upside down). Find all strobogrammatic numbers that are of length = n. For example,Given n = 2, return ["11","69","88","96"…