Word PatternGiven a pattern and a string str, find if str follows the same pattern. Here follow means a full match, such that there is a bijection between a letter in pattern and a non-empty word in
Move ZeroesGiven an array nums, write a function to move all 0’s to the end of it while maintaining the relative order of the non-zero elements. For example:1Given nums = [0, 1, 0, 3, 12], after call
Missing NumberGiven an array containing n distinct numbers taken from 0, 1, 2, …, n, find the one that is missing from the array. For example:1Given nums = [0, 1, 3] return 2. Note: Your algorithm sh
Ugly NumberWrite 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 ug
Add DigitsGiven a non-negative integer num, repeatedly add all its digits until the result has only one digit. For example:1Given num = 38, the process is like: 3 + 8 = 11, 1 + 1 = 2. Since 2 has onl
Power of TwoGiven an integer, write a function to determine if it is a power of two. 提示 解題應用 Math 規律觀查 BitManipulation AND Default:123func isPowerOfTwo(n int) bool { } 解答思路:一
Count PrimesCount the number of prime numbers less than a non-negative number, n. 提示 解題應用 HashTable Array Math 規律觀查 Default:123func countPrimes(n int) int {} 解答思路:非常典型的空間換取時間，因為
Happy NumberWrite an algorithm to determine if a number is “happy”. A happy number is a number defined by the following process: Starting with any positive integer, replace the number by the sum of t
Factorial Trailing ZeroesGiven an integer n, return the number of trailing zeroes in n!. Note: Your solution should be in logarithmic time complexity. 提示 解題應用 Math 觀查規律 Default:123func trai
Excel Sheet Column NumberRelated to question Excel Sheet Column Title Given a column title as appear in an Excel sheet, return its corresponding column number. For example:1234567A -> 1B -> 2C
Excel Sheet Column TitleGiven a positive integer, return its corresponding column title as appear in an Excel sheet. For Example:12345671 -> A2 -> B3 -> C...26 -> Z27 -> AA28 -> AB
Add BinaryGiven two binary strings, return their sum (also a binary string). For Example:123a = "11"b = "1"Return "100". 提示 解題應用 String 觀查規律 Math 觀查規律 Defaul
Roman to IntegerGiven a roman numeral, convert it to an integer. Input is guaranteed to be within the range from 1 to 3999. 提示 解題應用 Math 規律觀察 String 規律觀察 Default:12func romanToInt(s strin
Reverse IntegerReverse digits of an integer. Exmaple1:1x = 123, return 321 Exmaple2:1x = -123, return -321 Have you thought about this? Here are some good questions to ask before coding. Bonus points
Palindrome NumberDetermine whether an integer is a palindrome. Do this without extra space. Some hints: Could negative integers be palindromes? (ie, -1) If you are thinking of converting the integer