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…

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. Example…

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…

2020-01-03 12:01:46 问题描述: 问题求解: 确实可以当作数学题去做,但是要分类讨论什么的还是有点麻烦的. 这个时候万能的dfs上场了,直接暴力检索,真的太强了. int res = 0; public int numDupDigitsAtMostN(int N) { dfs(0, 0, N); return N - res + 1; } private void dfs(long curr, int used, int N) { if (curr > N) return; r…

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]) public class Sol…

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 < 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…

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]) 思路: 思路: 排列组合题. 设…