A Tic-Tac-Toe board is given as a string array board. Return True if and only if it is possible to reach this board position during the course of a valid tic-tac-toe game. The board is a 3 x 3 array, and consists of characters " ", "X"…

Given string S and a dictionary of words words, find the number of words[i] that is a subsequence of S. Example : Input: S = "abcde" words = ["a", "bb", "acd", "ace"] Output: 3 Explanation: There are three…

Let f(x) be the number of zeroes at the end of x!. (Recall that x! = 1 * 2 * 3 * ... * x, and by convention, 0! = 1.) For example, f(3) = 0 because 3! = 6 has no zeroes at the end, while f(11) = 2 because 11! = 39916800 has 2 zeroes at the end. Given…

We are given an array A of positive integers, and two positive integers L and R (L <= R). Return the number of (contiguous, non-empty) subarrays such that the value of the maximum array element in that subarray is at least Land at most R. Example : I…

题目:给定一个3*3的矩阵,是一个井字过三关游戏.开始为X先走,问你这个是不是一个合法的游戏.也就是,现在这种情况,能不能出现.如果有人赢了,那应该立即停止.那么可以知道X的步数和O的步数应该满足x==o+1或者x==o这种情况是允许的,这种情况是O赢.(x==o)这种情况是X赢(x==o+1).那么就可以知道 如果 ①.如果x>o+1(步数过多)||o>x(不符合x先行的规矩)  printf("no\n"); ②.如果是x赢了win(x)但是x!=o+1 不行 ③.如果…

题目如下: Tic-tac-toe is played by two players A and B on a 3 x 3 grid. Here are the rules of Tic-Tac-Toe: Players take turns placing characters into empty squares (" "). The first player A always places "X" characters, while the second pl…

题面: C. Team Tic Tac Toe Input file: standard input Output file: standard output Time limit: 1 second Memory limit: 256 megabytes   Farmer John owns 26 cows, which by happenstance all have names starting with different letters of the alphabet, so Farmer…

LeetCode Weekly Contest 8 415. Add Strings User Accepted: 765 User Tried: 822 Total Accepted: 789 Total Submissions: 1844 Difficulty: Easy Given two non-negative numbers num1 and num2 represented as string, return the sum of num1 and num2. Note: The…

1. Trees Tree is a recursive structure. 1.1 math nodes https://class.coursera.org/principlescomputing-001/wiki/view? page=trees 1.2 CODE无parent域的树 http://www.codeskulptor.org/#poc_tree.py class Tree: """ Recursive definition for trees plus…

leetcode weekly contest 43 leetcode649. Dota2 Senate leetcode649.Dota2 Senate 思路: 模拟规则round by round. class Solution { public: string predictPartyVictory(string senate) { int len = senate.size(); int r = 0; int d = 0; int i = 0; while(1) { if(senate[…