题意: 给定n,和一个长度为n的序列. 让你在这n个数中找长度尽可能长的fib数列. 思路: 这题的数字是在1e9范围内的,所以最长的可能存在的fib数列官方的解释是90左右.有一种情况除外,就是0的个数比较多的情况下. 而决定fib数列的是开头的两个数字,以及顺序,介于n是1000的范围我们就可以暴力开头的两个数字啦.这题要注意0的情况,如果整个序列都是0的话,那么复杂度就是1e9了,所以本人先unique了一下,然后每次从unique完的数组里边取材,这样就避免了0的问题同时也某些程度上减少…

题意:1000个元素,每个元素的大小-1e9<=a[i]<=1e9,然后让你重新安排这些元素的位置 获得最长的前缀斐波那契数列 分析:枚举第一个元素和第二个元素,因为在题目元素的范围内,最多形成长度为90的斐波那契数列 除非有全0的情况出现,这种情况会达到长度1000 所以这种情况特判一下(记录一下零元素的个数就行了) 然后枚举是n^2的 找元素是90,然后找的时候,我用的map来找 所以时间复杂度是略大是O(90n^2logn) 所以由于不可能每次都找到90,所以均摊比较小,这题时限是3s,…

Fibonacci-ish Yash has recently learnt about the Fibonacci sequence and is very excited about it. He calls a sequence Fibonacci-ish if the sequence consists of at least two elements f0 and f1 are arbitrary fn + 2 = fn + 1 + fn for all n ≥ 0. You are…

D. Fibonacci-ish time limit per test 3 seconds memory limit per test 512 megabytes input standard input output standard output Yash has recently learnt about the Fibonacci sequence and is very excited about it. He calls a sequence Fibonacci-ish if th…

Fibonacci-ish Yash has recently learnt about the Fibonacci sequence and is very excited about it. He calls a sequence Fibonacci-ish if the sequence consists of at least two elements f0 and f1 are arbitrary fn + 2 = fn + 1 + fn for all n ≥ 0. You are…

上一次我们拿学校的URP做了个小小的demo.... 其实我们还可以把每个学生的证件照爬下来做成一个证件照校花校草评比 另外也可以写一个物理实验自动选课... 但是出于多种原因,,还是绕开这些敏感话题.. 今天,我们来扒一下cf的题面! PS:本代码不是我原创 1. 必要的分析 1.1 页面的获取 一般情况CF的每一个 contest 是这样的: 对应的URL是:http://codeforces.com/contest/xxx 还有一个Complete problemset页面,它是这样的:…

http://codeforces.com/contest/738/problem/D Galya is playing one-dimensional Sea Battle on a 1 × n grid. In this game a ships are placed on the grid. Each of the ships consists of bconsecutive cells. No cell can be part of two ships, however, the shi…

http://codeforces.com/contest/738/problem/C Vasya is currently at a car rental service, and he wants to reach cinema. The film he has bought a ticket for starts in t minutes. There is a straight road of length s from the service to the cinema. Let's…

http://codeforces.com/contest/738/problem/A Polycarp has interviewed Oleg and has written the interview down without punctuation marks and spaces to save time. Thus, the interview is now a string s consisting of n lowercase English letters. There is…

http://codeforces.com/problemset/problem/662/A 题目大意: 给定n(n <= 500000)张卡片,每张卡片的两个面都写有数字,每个面都有0.5的概率是在正面,各个卡牌独立.求把所有卡牌来玩Nim游戏,先手必胜的概率. (⊙o⊙)-由于本人只会在word文档里写公式,所以本博客是图片格式的. Code #include <cstdio> #include <cstring> #include <algorithm> u…