You are playing the following Bulls and Cows game with your friend: You write a 4-digit secret number and ask your friend to guess it, each time your friend guesses a number, you give a hint, the hint tells your friend how many digits are in the corr…

You are playing the following Bulls and Cows game with your friend: You write a 4-digit secret number and ask your friend to guess it. Each time your friend guesses a number, you give a hint. The hint tells your friend how many digits are in the corr…

题意: 给出两个数字,输出(1)有多少位是相同的(2)有多少位不在正确的位置上. 思路: 扫一遍,统计相同的,并且将两串中不同的数的出现次数分别统计起来,取小者之和就是第2个答案了. class Solution { public: string getHint(string secret, string guess) { ; ,sizeof(int)*N); ,sizeof(int)*N); , wrong=; ; i<secret.size(); i++) { if(secret[i]==g…

题意: 给一个数组,其中有一个元素的出现次数已经超过数组的一半大小,请找出这个元素? 思路: 可以扫一遍数组,将这个出现次数过多的元素抵消其他的元素,最后必定留下1个以上的元素,就是它自己了. python3 扫一遍 class Solution(object): def majorityElement(self, nums): """ :type nums: List[int] :rtype: int """ idx,cnt,cur=0,0,0…

题意: 判断是一个数的质因子仅含有2,3,5这3个. 思路: 因子2比较容易解决,num/=num-(num&num-1)就可以了.3和5的需要通过循环来另判. C++ class Solution { public: bool isUgly(int num) { ) return true; ) return false; num/=num-(num&num-); ==) num/=; ==) num/=; ; } }; AC代码 python3 class Solution(objec…

题意: 给一个含有n个整数的数组,数组中的元素应该是0-n.现在缺了其中某1个,找出缺少的那个整数? 思路: 0-n的总和是可以直接计算的,而缺少的那个就是sum减去数组的和. int missingNumber(vector<int>& nums) { ; ; i<nums.size(); i++) sum+=i+-nums[i]; return sum; } AC代码…

题意: 给出两个字符串s和t,判断串t是否为s打乱后的串. 思路: 如果返回的是true,则两个串的长度必定相等,所有字符出现的次数一样.那么可以统计26个字母的次数来解决,复杂度O(n).也可以排序后逐个比对,复杂度O(nlogn). 第一种方法: class Solution { public: bool isAnagram(string s,string t) { if(s.size()!=t.size()) return false; ][]={}; ; i<s.size(); i++)…

题意: 给定一个整型数组nums,要求将其中所有的0移动到末尾,并维护所有非0整数的相对位置不变. 思路: 扫一遍,两个指针维护0与非0的交界,将非0的数向前赋值就行了. C++ class Solution { public: void moveZeroes(vector<int>& nums) { ; ; i<nums.size(); i++) ) nums[idx++]=nums[i]; while(idx<nums.size()) nums[idx++]=; } }…

[LeetCode]299. Bulls and Cows 解题报告(Python) 作者: 负雪明烛 id: fuxuemingzhu 个人博客: http://fuxuemingzhu.cn/ 题目地址:https://leetcode.com/problems/bulls-and-cows/description/ 题目描述: You are playing the following Bulls and Cows game with your friend: You write down…

一. 题目描写叙述 You are playing the following Bulls and Cows game with your friend: You write down a number and ask your friend to guess what the number is. Each time your friend makes a guess, you provide a hint that indicates how many digits in said gues…