Codeforces Round #747 (Div. 2) A. Consecutive Sum Riddle 思路分析: 一开始想起了那个公式\(l + (l + 1) + - + (r − 1) + r = (l + r)(r - l + 1) / 2\). 然后一看令\(l + r = 1\)最合适,那么就有\(l = r - 1\),一代入就得到\(r = n, l = -n + 1\). 没想通为什么没有一眼看出来. 代码 #include <bits/stdc++.h> #def…

比赛地址 A(水题) 题目链接 题目: 给出指定\(n\),求解出一段区间\([l,r]\)使得\(\sum\limits_{i=l}^ri=n\) 解析: 从点0,1两点作为起点分别向左右延伸长度,每次延伸单位长度时,这段区间和也加1,因此答案为\([1-n,n]\) #include<bits/stdc++.h> using namespace std; int main() { int T; long long t; scanf("%d", &T); whi…

谢天谢地,还好没掉分,还加了8分,(8分再小也是加啊)前期刚开始有点卡,不过在尽力的调整状态之后,还是顺利的将前面的水题过完了,剩下的E2和F题就过不去了,估计是能力问题,自己还是得认真补题啦. E2. Rubik's Cube Coloring (hard version) 这个题是在上一题的基础上出现的,E1的就很简单,一个完全二叉树,每个点都没有染色,求不同染色方案的方案数.显然的是在第一个点的颜色确定后,后面所有点的颜色都只有4种选择,也就是无论父节点选了什么颜色,该节点都有且仅有四种选…

Codeforces Round #366 (Div. 2) A I hate that I love that I hate it水题 #I hate that I love that I hate it n = int(raw_input()) s = "" a = ["I hate that ","I love that ", "I hate it","I love it"] for i in ran…

Codeforces Round #354 (Div. 2) Problems     # Name     A Nicholas and Permutation standard input/output 1 s, 256 MB    x3384 B Pyramid of Glasses standard input/output 1 s, 256 MB    x1462 C Vasya and String standard input/output 1 s, 256 MB    x1393…

直达–>Codeforces Round #368 (Div. 2) A Brain’s Photos 给你一个NxM的矩阵,一个字母代表一种颜色,如果有”C”,”M”,”Y”三种中任意一种就输出”#Color”,如果只有”G”,”B”,”W”就输出”#Black&White”. #include <cstdio> #include <cstring> using namespace std; const int maxn = 200; const int INF =…

 cf之路,1,Codeforces Round #345 (Div. 2) ps:昨天第一次参加cf比赛,比赛之前为了熟悉下cf比赛题目的难度.所以做了round#345连试试水的深浅.....       其实这个应该是昨天就写完的,不过没时间了,就留到了今天.. 地址:http://codeforces.com/contest/651/problem/A A. Joysticks time limit per test 1 second memory limit per test 256…

Codeforces Round #279 (Div. 2) 做得我都变绿了! Problems     # Name     A Team Olympiad standard input/output 1 s, 256 MB  x2377 B Queue standard input/output 2 s, 256 MB  x1250 C Hacking Cypher standard input/output 1 s, 256 MB  x740 D Chocolate standard in…

Codeforces Round #262 (Div. 2) 1003 C. Present time limit per test 2 seconds memory limit per test 256 megabytes input standard input output standard output Little beaver is a beginner programmer, so informatics is his favorite subject. Soon his info…

Codeforces Round #262 (Div. 2) 1004 D. Little Victor and Set time limit per test 1 second memory limit per test 256 megabytes input standard input output standard output Little Victor adores the sets theory. Let us remind you that a set is a group of…