摘要:Given an array that has n integers, count the number of ways to split all elements of this array into 3 contiguous parts so that the sum of each part 阅读全文
posted @ 2019-10-29 02:10 lz87 阅读 (8) 评论 (0) 编辑
摘要:You are climbing a stair case. It takes n steps to reach to the top. Each time you can either climb 1 or 2 steps. In how many distinct ways can you cl 阅读全文
posted @ 2019-10-28 10:23 lz87 阅读 (12) 评论 (0) 编辑
摘要:Consider a multiset of integers S, the union of n closed intervals of positive integers: S = [l1..r1] ∪ [l2..r2] ∪ · · · ∪ [ln..rn](recall that a clos 阅读全文
posted @ 2019-10-25 05:55 lz87 阅读 (10) 评论 (0) 编辑
摘要:Smaller input size: https://codeforces.com/contest/1249/problem/D1 Big input size: https://codeforces.com/contest/1249/problem/D2 Given n segments on 阅读全文
posted @ 2019-10-25 04:56 lz87 阅读 (47) 评论 (0) 编辑
摘要:You are given a string consisting of the letters x and y, such as xyxxxyxyy. In addition, you have an operation called flip, which changes a single x  阅读全文
posted @ 2019-10-25 00:48 lz87 阅读 (11) 评论 (0) 编辑
摘要:You are given a string containing only 4 kinds of characters 'Q', 'W', 'E' and 'R'. A string is said to be balanced if each of its characters appears  阅读全文
posted @ 2019-10-21 22:30 lz87 阅读 (55) 评论 (0) 编辑
摘要:Given n kinds of present and m boxes. Find out the different ways to pack all boxes with presents, using the following rules. 1. Each box can not have 阅读全文
posted @ 2019-10-18 11:25 lz87 阅读 (6) 评论 (0) 编辑
摘要:Given an array nums of positive integers, return the longest possible length of an array prefix of nums, such that it is possible to remove exactly on 阅读全文
posted @ 2019-10-14 03:10 lz87 阅读 (71) 评论 (0) 编辑
摘要:A die simulator generates a random number from 1 to 6 for each roll. You introduced a constraint to the generator such that it cannot roll the number  阅读全文
posted @ 2019-10-14 01:42 lz87 阅读 (215) 评论 (0) 编辑
摘要:Your music player contains N different songs and she wants to listen to L (not necessarily different) songs during your trip. You create a playlist so 阅读全文
posted @ 2019-10-11 11:09 lz87 阅读 (18) 评论 (0) 编辑