[题解] 第一眼看题飞快地想到一种做法,然后假掉了. 这道题其实是主席树的模板题来着.但是也有别的水法. 我们可以发现每个位置的查询区间是[1,min(a[i],i-1)],所以我们可以把查询区间按照右端点排序.开一个权值树状数组记录前i个a[i]的出现情况.我们从1到n按顺序插入a[i],每个位置上都统计min(a[j],j-1)=i的j的答案. #include<cstdio> #include<algorithm> #define rg register #define N…

Educational Codeforces Round 41 (Rated for Div. 2) E. Tufurama (CDQ分治 求 二维点数) time limit per test 2 seconds memory limit per test 256 megabytes input standard input output standard output One day Polycarp decided to rewatch his absolute favourite epi…

Educational Codeforces Round 41  D. Pair Of Lines 考虑先把凸包找出来,如果凸包上的点数大于\(4\)显然不存在解,小于等于\(2\)必然存在解 否则枚举凸包上两个点连线,判断剩余点能否被一条线覆盖即可 view code #pragma GCC optimize("O3") #pragma GCC optimize("Ofast,no-stack-protector") #include<bits/stdc++…

这场没打又亏疯了!!! A - Tetris : 类似俄罗斯方块,模拟一下就好啦. #include<bits/stdc++.h> #define fi first #define se second #define mk make_pair #define pii pair<int,int> using namespace std; typedef long long ll; const int inf=0x3f3f3f3f; const ll INF=0x3f3f3f3f3f3…

最近打的比较少...就只有这么点题解了. A. Tetris time limit per test 1 second memory limit per test 256 megabytes input standard input output standard output You are given a following process. There is a platform with n columns. 1 × 1 squares are appearing one after a…

A. Tetris 题意 俄罗斯方块,问能得多少分. 思路 即求最小值 Code #include <bits/stdc++.h> #define F(i, a, b) for (int i = (a); i < (b); ++i) #define F2(i, a, b) for (int i = (a); i <= (b); ++i) #define dF(i, a, b) for (int i = (a); i > (b); --i) #define dF2(i, a,…

http://codeforces.com/contest/961 B题 可以将长度为k的连续区间转化成1 求最大和 解析 简单尺取 #include <stdio.h> #include <math.h> #include <string.h> #include <stdlib.h> #include <iostream> #include <sstream> #include <algorithm> #include…

题意比较麻烦略 题解:枚举前缀的中点,二分最远能扩展的地方,lcp来check,然后线段树维护每个点最远被覆盖的地方,然后查询线段树即可 //#pragma GCC optimize(2) //#pragma GCC optimize(3) //#pragma GCC optimize(4) //#pragma GCC optimize("unroll-loops") //#pragma comment(linker, "/stack:200000000") //#…

由于之前打过了这场比赛的E题,而后面两道题太难,所以就手速半个多小时A了前4题. 就当练手速吧,不过今天除了C题数组开小了以外都是1A A Tetris 题意的抽象解释可以在Luogu里看一下(话说现在Luogu是真的好用) 非常入门的一道题,建模转化后扫一遍找出最小值即可 CODE #include<cstdio> #include<cstring> using namespace std; const int N=1005; int a[N],n,m,x,ans; inline…

#include <vector> #include <iostream> #include <algorithm> using namespace std; typedef long long ll; ; ll x[N], y[N]; int n; bool gx(int a, int b, int c, int d) { return (x[b] - x[a])*(y[d] - y[c]) == (x[d] - x[c])*(y[b] - y[a]); } int…

//暴力 #include <iostream> #include <algorithm> #include <string> using namespace std; ; string s1[N], s2[N], s3[N], s4[N]; int a[N][N], b[N][N]; int main() { int n; cin >> n; ; i<n; i++) cin >> s1[i]; cin.get(); ; i<n; i…

前缀后缀和搞一搞,然后枚举一下区间,找出最大值 #include <iostream> #include <algorithm> using namespace std; ; int a[maxn], f[maxn], b[maxn], c[maxn]; int main() { ios::sync_with_stdio(false); int n, k; cin >> n >> k; ; i <= n; i++) cin >> a[i];…

[题意概述] 给出平面上的10W个点,要求判断这些点能否被两条直线穿过,即一个点至少在一条直线上. [题解] 思路很快可以想到.取3个不共线的点,它们形成一个三角形:如果有解,其中的一条直线一定与三角形的一条边重合.于是用这三条边一一进行验证即可. 第一次交被卡了精度,后来意识到判断三个点是否共线写丑了,其实并不需要求解析式.直接运用相似三角形,移项变成乘法即可. #include<cstdio> #include<algorithm> #include<cstring>…

[链接] 我是链接,点我呀:) [题意] 在这里输入题意 [题解] 如果点的个数<=3 那么直接输出有解. 否则. 假设1,2最后会在一条直线上,则把这条直线上的点都删掉. 看看剩余的点是否在同一条直线上,是的话输出有解. 否则再假设1,3最后会在一条直线上,同样的看看这条直线之外的点是否 在同一条直线上. 是的话同样输出有解. 否则,因为前两种都没有解,那就说明1和2不共线,且1和3不共线,而只有两条线,且要穿过所有点. 那么就说明2,3肯定是只能在一条线上了,然后1分另外一条线. 把2,3用…

D. Pair Of Lines time limit per test 2 seconds memory limit per test 256 megabytes input standard input output standard output You are given n points on Cartesian plane. Every point is a lattice point (i. e. both of its coordinates are integers), and…

Educational Codeforces Round 17 A. k-th divisor 水题,把所有因子找出来排序然后找第\(k\)大 view code //#pragma GCC optimize("O3") //#pragma comment(linker, "/STACK:1024000000,1024000000") #include<bits/stdc++.h> using namespace std; function<voi…

[Educational Codeforces Round 16]E. Generate a String 试题描述 zscoder wants to generate an input file for some programming competition problem. His input is a string consisting of n letters 'a'. He is too lazy to write a generator so he will manually ge…

[Educational Codeforces Round 16]D. Two Arithmetic Progressions 试题描述 You are given two arithmetic progressions: a1k + b1 and a2l + b2. Find the number of integers x such that L ≤ x ≤ R andx = a1k' + b1 = a2l' + b2, for some integers k', l' ≥ 0. 输入 Th…

[Educational Codeforces Round 16]C. Magic Odd Square 试题描述 Find an n × n matrix with different numbers from 1 to n2, so the sum in each row, column and both main diagonals are odd. 输入 The only line contains odd integer n (1 ≤ n ≤ 49). 输出 Print n lines…

[Educational Codeforces Round 16]B. Optimal Point on a Line 试题描述 You are given n points on a line with their coordinates xi. Find the point x so the sum of distances to the given points is minimal. 输入 The first line contains integer n (1 ≤ n ≤ 3·105)…

[Educational Codeforces Round 16]A. King Moves 试题描述 The only king stands on the standard chess board. You are given his position in format "cd", where c is the column from 'a' to 'h' and dis the row from '1' to '8'. Find the number of moves perm…

Educational Codeforces Round 6 C. Pearls in a Row 题意:一个3e5范围的序列:要你分成最多数量的子序列,其中子序列必须是只有两个数相同, 其余的数只能出现一次. 策略: 延伸:这里指的延伸如当发现1-1如果以最后出现重叠的数为右边界则就表示左延伸,若以1.0.1..0第二个0前一个位置作为右边界就为右延伸: 开始时想是右延伸,考虑到可能只出现一组两个数相同,认为向左延伸会出错,但是直接WA了之后,发现这并不是题目的坑点(其实只需将最后一组改成左右…

Educational Codeforces Round 9 Longest Subsequence 题目描述:给出一个序列,从中抽出若干个数,使它们的公倍数小于等于\(m\),问最多能抽出多少个数,并输出方案与公倍数. solution 枚举每一个数,将它的倍数的答案加一,最大值就是答案. 时间复杂度:\(O(nlogn)\) Thief in a Shop 题目描述:给出\(n\)中物品与它们的价值,每种物品都有无限个,问从中拿出\(m\)个,价值有可能是什么,输出所有的价值. soluti…

Educational Codeforces Round 37 这场有点炸,题目比较水,但只做了3题QAQ.还是实力不够啊! 写下题解算了--(写的比较粗糙,细节或者bug可以私聊2333) A. Water The Garden 题意:给你一个长度为\(n\)的池子,告诉你哪些地方一开始有水, 每秒可以向左和向右增加一格的水, 问什么时候全部充满水.(\(n \le 200\)) 题解:按题意模拟.每次进来一个水龙头,就更新所有点的答案 (取\(min\)).最 后把所有点取个\(max\)就…

Problem   Educational Codeforces Round 60 (Rated for Div. 2) - C. Magic Ship Time Limit: 2000 mSec Problem Description Input Output The only line should contain the minimal number of days required for the ship to reach the point (x2,y2)(x2,y2). If it…

Problem   Educational Codeforces Round 60 (Rated for Div. 2) - D. Magic Gems Time Limit: 3000 mSec Problem Description Input The input contains a single line consisting of 2 integers N and M (1≤N≤10^18, 2≤M≤100). Output Print one integer, the total n…

616A - Comparing Two Long Integers    20171121 直接暴力莽就好了...没什么好说的 #include<stdlib.h> #include<stdio.h> #include<math.h> #include<cstring> #include<iostream> #include<algorithm> using namespace std; string a,b;int sa,sb;…

Educational Codeforces Round 43 (Rated for Div. 2) https://codeforces.com/contest/976 A #include<bits/stdc++.h> using namespace std; #define lson l,mid,rt<<1 #define rson mid+1,r,rt<<1|1 #define IT set<ll>::iterator #define sqr(x)…

Educational Codeforces Round 35 (Rated for Div. 2) https://codeforces.com/contest/911 A 模拟 #include<bits/stdc++.h> using namespace std; #define lson l,mid,rt<<1 #define rson mid+1,r,rt<<1|1 #define IT set<ll>::iterator #define sqr(…

Codeforces Educational Codeforces Round 44 (Rated for Div. 2) F. Isomorphic Strings 题目连接: http://codeforces.com/contest/985/problem/F Description You are given a string s of length n consisting of lowercase English letters. For two given strings s an…