题目描述: Given a non-negative integer n, count all numbers with unique digits, x, where 0 ≤ x < 10n. Example:Given n = 2, return 91. (The answer should be the total numbers in the range of 0 ≤ x < 100, excluding [11,22,33,44,55,66,77,88,99]) 解题思路: This…

Given a non-negative integer n, count all numbers with unique digits, x, where 0 ≤ x < 10n. Example: Input: 2 Output: 91 Explanation: The answer should be the total numbers in the range of 0 ≤ x < 100,   excluding 11,22,33,44,55,66,77,88,99 Runtime:…

作者: 负雪明烛 id: fuxuemingzhu 个人博客: http://fuxuemingzhu.cn/ 目录 题目描述 题目大意 解题方法 日期 题目地址:https://leetcode.com/problems/count-numbers-with-unique-digits/description/ 题目描述 Given a non-negative integer n, count all numbers with unique digits, x, where 0 ≤ x <…

题目描述: Given a non-negative integer n, count all numbers with unique digits, x, where 0 ≤ x < 10n. 解题分析: 题目要就就是找出 0≤ x < 10n中各位数字都不相同的数的个数.要接触这道题只需要理解: 1.设f(n)表示n为数字中各位都不相同的个数,则有countNumbersWithUniqueDigits(n)=f(1)+f(2)+……+f(n)=f(n)+countNumbersWithU…

Given a non-negative integer n, count all numbers with unique digits, x, where 0 ≤ x < 10n. Example:Given n = 2, return 91. (The answer should be the total numbers in the range of 0 ≤ x < 100, excluding [11,22,33,44,55,66,77,88,99]) 代码如下: public cla…

给定一个非负整数 n,计算各位数字都不同的数字 x 的个数,其中 0 ≤ x < 10n.示例:给定 n = 2,返回 91.(答案应该是除[11,22,33,44,55,66,77,88,99]外,0 ≤ x < 100 间的所有数字) 详见:https://leetcode.com/problems/count-numbers-with-unique-digits/description/ C++: class Solution { public: int countNumbersWith…

Given a non-negative integer n, count all numbers with unique digits, x, where 0 ≤ x < 10n. Example: Given n = 2, return 91. (The answer should be the total numbers in the range of 0 ≤ x < 100, excluding [11,22,33,44,55,66,77,88,99]) Hint: A direct…

Given a non-negative integer n, count all numbers with unique digits, x, where 0 ≤ x < 10n. Example: Given n = 2, return 91. (The answer should be the total numbers in the range of 0 ≤ x < 100, excluding [11,22,33,44,55,66,77,88,99]) Analysis: A num…

Given a non-negative integer n, count all numbers with unique digits, x, where 0 ≤ x < 10^n. Example:Given n = 2, return 91. (The answer should be the total numbers in the range of 0 ≤ x < 100, excluding [11,22,33,44,55,66,77,88,99]) 思路:DP dp[i]表示10…

Given a non-negative integer n, count all numbers with unique digits, x, where 0 ≤ x < 10n. Example: Input: 2 Output: 91 Explanation: The answer should be the total numbers in the range of 0 ≤ x < 100,   excluding 11,22,33,44,55,66,77,88,99 给定一个非负整数…

Given a non-negative integer n, count all numbers with unique digits, x, where 0 ≤ x < 10n. Example:Given n = 2, return 91. (The answer should be the total numbers in the range of 0 ≤ x < 100, excluding [11,22,33,44,55,66,77,88,99]) public class Sol…

https://leetcode.com/problems/count-numbers-with-unique-digits/ 给定一个n,计算[0,10^n]中十进制中每一位都不相同的数的数目. class Solution{ public: int countNumbersWithUniqueDigits(int n){ ; , n); ; i--){ ; ; j>; j--) tmp *= -i+j+; res+=tmp; } ; } };…

Given a non-negative integer n, count all numbers with unique digits, x, where 0 ≤ x < 10n. Example:Given n = 2, return 91. (The answer should be the total numbers in the range of 0 ≤ x < 100, excluding [11,22,33,44,55,66,77,88,99]) 思路: 思路: 排列组合题. 设…

题目描述: Description: Count the number of prime numbers less than a non-negative number, n. 解题思路: Let's start with a isPrime function. To determine if a number is prime, we need to check if it is not divisible by any number less than n. The runtime comp…

题目如下: Given a positive integer N, return the number of positive integers less than or equal to N that have at least 1 repeated digit. Example 1: Input: 20 Output: 1 Explanation: The only positive number (<= 20) with at least 1 repeated digit is 11. E…

题目描述: The count-and-say sequence is the sequence of integers beginning as follows: 1, 11, 21, 1211, 111221, ... 1 is read off as "one 1" or 11. 11 is read off as "two 1s" or 21. 21 is read off as "one 2, then one 1" or 1211.…

https://leetcode.com/problems/numbers-with-repeated-digits/ 与leetcode_357. Count Numbers with Unique Digits有一些相似的地方. 给定N,计算小于等于N且至少有一个重复数位的数的数目. 可转化为计算小于等于N且所有数位不相同的数的数目.且可分为两部分, 位数与N相同且小于等于N且所有数位不相同的数的数目: 位数小于N且所有数位不相同的数的数目. 难点在于第1部分. 解法一: 使用dfs计算第一…

Note: 后面数字n表明刷的第n + 1遍, 如果题目有**, 表明有待总结 Conclusion questions: [LeetCode] questions conclustion_BFS, DFS LeetCode questions conclustion_Path in Tree [LeetCode] questions conlusion_InOrder, PreOrder, PostOrder traversal [LeetCode] questions for Dynamic…

LeetCode--Find All Numbers Disappeared in an Array Question Given an array of integers where 1 ≤ a[i] ≤ n (n = size of array), some elements appear twice and others appear once. Find all the elements of [1, n] inclusive that do not appear in this arr…

索引:[LeetCode] Leetcode 题解索引 (C++/Java/Python/Sql) Github: https://github.com/illuz/leetcode 038. Count and Say (Easy) 链接: 题目:https://leetcode.com/problems/Count-and-Say/ 代码(github):https://github.com/illuz/leetcode 题意: 数数.第一个是 1,第二个是数前一个数:1 个 1,就是 11…

Count Numbers 时间限制: 8 Sec  内存限制: 128 MB提交: 43  解决: 19[提交] [状态] [讨论版] [命题人:admin] 题目描述 Now Alice wants to sum up all integers whose digit sum is exactly ab .However we all know the number of this kind of integers are unlimited. So she decides to sum u…

Count Numbers 时间限制: 8 Sec  内存限制: 128 MB 题目描述 Now Alice wants to sum up all integers whose digit sum is exactly ab .However we all know the number of this kind of integers are unlimited. So she decides to sum up all these numbers whose each digit is n…

说来惭愧,已经四个月没有切 leetcode 上的题目了. 虽然工作中很少(几乎)没有用到什么高级算法,数据结构,但是我一直坚信 "任何语言都会过时,只有数据结构和算法才能永恒".leetcode 上的题目,截止目前切了 137 道(all solutions),只写过 6 篇题解,所以我会写题解的一般都是自认为还蛮有意思或者蛮典型的题目,就比如这道题. 题目链接:Count of Smaller Numbers After Self 这道题很有意思,给出一个数组,返回一个新的数组,新…

说来惭愧,已经四个月没有切 leetcode 上的题目了. 虽然工作中很少(几乎)没有用到什么高级算法,数据结构,但是我一直坚信 "任何语言都会过时,只有数据结构和算法才能永恒".leetcode 上的题目,截止目前切了 137 道(all solutions),只写过 6 篇题解,所以我会写题解的一般都是自认为还蛮有意思或者蛮典型的题目,就比如这道题. 题目链接:Count of Smaller Numbers After Self 这道题很有意思,给出一个数组,返回一个新的数组,新…

原题链接在这里:https://leetcode.com/problems/count-of-smaller-numbers-after-self/ 题目: You are given an integer array nums and you have to return a new counts array. The counts array has the property where counts[i] is the number of smaller elements to the r…

Given a complete binary tree, count the number of nodes. Definition of a complete binary tree from Wikipedia: In a complete binary tree every level, except possibly the last, is completely filled, and all nodes in the last level are as far left as po…

Description: Count the number of prime numbers less than a non-negative number, n. 解题思路: 空间换时间,开一个空间为n的数组,因为非素数至少可以分解为一个素数,因此遇到素数的时候,将其有限倍置为非素数,这样动态遍历+构造下来,没有被设置的就是素数. public int countPrimes(int n) { if (n <= 2) return 0; boolean[] notPrime = new boo…

The count-and-say sequence is the sequence of integers beginning as follows: 1, 11, 21, 1211, 111221, ... 1 is read off as "one 1" or 11. 11 is read off as "two 1s" or 21. 21 is read off as "one 2, then one 1" or 1211. Given…

题目描述: Compare two version numbers version1 and version2.If version1 > version2 return 1, if version1 < version2 return -1, otherwise return 0. You may assume that the version strings are non-empty and contain only digits and the . character.The . ch…

问题描述: You are given two linked lists representing two non-negative numbers. The digits are stored in reverse order and each of their nodes contain a single digit. Add the two numbers and return it as a linked list. Input: (2 -> 4 -> 3) + (5 -> 6…