#-*- coding: UTF-8 -*-#给定一个整数N,那么N的阶乘N!末尾有多少个0? 比如:N=10,N!=3628800,N!的末尾有2个0.#所有的尾部的0可以看做都是2*5得来的,所以通过计算所有的因子中2和5的个数就可以知道尾部0的个数.#实际上,2的个数肯定是足够的,所以只需计算5的个数即可.#要注意,25=5*5是有两个5的因子:125=5*5*5有3个5的因子.比如,计算135!末尾0的个数.#首先135/5 = 27,说明135以内有27个5的倍数:27/5=5,说明1…
Factorial Trailing Zeroes Given an integer n, return the number of trailing zeroes in n!. Note: Your solution should be in logarithmic time complexity. Credits:Special thanks to @ts for adding this problem and creating all test cases. 对n!做质因数分解n!=2x*…
Given an integer n, return the number of trailing zeroes in n!. Example 1: Input: 3 Output: 0 Explanation: 3! = 6, no trailing zero. Example 2: Input: 5 Output: 1 Explanation: 5! = 120, one trailing zero. Note: Your solution should be in logarithmic…
Given an integer n, return the number of trailing zeroes in n!. Note: Your solution should be in logarithmic time complexity. 题目标签:Math 题目要求我们找到末尾0的数量. 只有当有10的存在,才会有0,比如 2 * 5 = 10; 4 * 5 = 20; 5 * 6 = 30; 5 * 8 = 40 等等,可以发现0 和 5 的联系. 所以这一题也是在问 n 里有多…
Given an integer n, return the number of trailing zeroes in n!. Note: Your solution should be in logarithmic time complexity. 解题思路: 计算n能达到的5的最大次幂,算出在这种情况下能提供的5的个数,然后减去之后递归即可,JAVA实现如下: static public int trailingZeroes(int n) { if(n<25) return n/5; lon…
一天一道LeetCode 本系列文章已全部上传至我的github,地址:ZeeCoder's Github 欢迎大家关注我的新浪微博,我的新浪微博 欢迎转载,转载请注明出处 (一)题目 Given an integer n, return the number of trailing zeroes in n!. Note: Your solution should be in logarithmic time complexity. (二)解题 题目大意:求n的阶乘算出来的数尾部有多少个0.如5…
题目 Given an integer n, return the number of trailing zeroes in n!. Note: Your solution should be in logarithmic time complexity. 分析 Note中提示让用对数的时间复杂度求解,那么如果粗暴的算出N的阶乘然后看末尾0的个数是不可能的. 所以仔细分析,N! = 1 * 2 * 3 * ... * N 而末尾0的个数只与这些乘数中5和2的个数有关,因为每出现一对5和2就会产生…
Given an integer n, return the number of trailing zeroes in n!. Note: Your solution should be in logarithmic time complexity. 主要是思考清楚计算过程: 将一个数进行因式分解,含有几个5就可以得出几个0(与偶数相乘). 代码很简单. public class Solution { public int trailingZeroes(int n) { int result =…
题目描述: Given an integer n, return the number of trailing zeroes in n!. Note: Your solution should be in logarithmic time complexity. 解题思路: 对于阶乘而言,也就是1*2*3*...*n[n/k]代表1~n中能被k整除的个数那么很显然[n/2] > [n/5] (左边是逢2增1,右边是逢5增1)[n/2^2] > [n/5^2](左边是逢4增1,右边是逢25增1)…
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 递归 循环 日期 题目描述 Given an integer n, return the number of trailing zeroes in n!. Example 1: Input: 3 Output: 0 Explanation: 3! = 6, no trailing zero. Example 2: Input: 5 Output: 1 Expl…