B. Seating On Bus 题目连接: http://www.codeforces.com/contest/660/problem/B Description Consider 2n rows of the seats in a bus. n rows of the seats on the left and n rows of the seats on the right. Each row can be filled by two people. So the total capac…

A. Co-prime Array 题目连接: http://www.codeforces.com/contest/660/problem/A Description You are given an array of n elements, you must make it a co-prime array in as few moves as possible. In each move you can insert any positive integral number you want…

司老大当时教了一种姿势枚举连续K个0,说实话当时比赛写这题完全蒙了 纵然后来知道思路还是写了一段时间 真的是.. 题目大意 n长度的序列,由0 1构成 我们可以改变 k个0为1 求可以得到的最长连续1序列的长度 既然求连续1 我们贪心连续k个0 枚举端点 左端点0设置为0 右端点0设置为 n+1 中间统计一下 最长长度和改变的0的位置就OK了 #include<cstdio> #include<map> //#include<bits/stdc++.h> #includ…

A. Co-prime Array 题意:给你一个数列,要求构造两两相邻之间的数互质的数列,可以插入的数的小于10的9次方 思路:其实可以选择靠近10的9次方的最大的三个素数.然后按我下面的方法做就可以了,我这里选的三个素数不是最大的,数据有点水,就水过了 #include<cstdio> #include<cstring> #include<cmath> ; int num[qq]; ]; int gcd(int x,int y) { ?x:gcd(y,x%y); }…

http://codeforces.com/contest/660/problem/D 这个题据说是很老的题了 然而我现在才知道做法 用map跑了1953ms: 题目大意 给你n个点的坐标 求这些点能组成多少个位置不同的四边形 我们统计两个点之间的中点坐标  假如有n对点的中点重合 那么我们就知道这里面有(n-1)*n/2个平行四边形 就这样搞喽. PS:说实话typedef pair<double,double> pdd; 这语句让我想到了骚猪PDD 笑死了. #include<cst…

题目链接: http://codeforces.com/contest/660/problem/C 题意: 将最多k个0变成1,使得连续的1的个数最大 题解: 二分连续的1的个数x.用前缀和判断区间[i,i+x-1]里面0的个数是否小于等于k. 代码: #include<iostream> #include<cstdio> #include<vector> #include<cstring> using namespace std; ; int n,k; i…

A. Co-prime Array http://codeforces.com/contest/660/problem/A 题意:给出一段序列,插进一些数,使新的数列两两成互质数,求插最少的个数,并输出这个序列. 思路:最优的就是插入1,1与非1的数都互质. #include<bits/stdc++.h> using namespace std; int gcd(int a,int b){ ?a:gcd(b,a%b); } int main(){ ,a[],b[]; scanf("%…

E. Different Subsets For All Tuples 题目连接: http://www.codeforces.com/contest/660/problem/E Description For a sequence a of n integers between 1 and m, inclusive, denote f(a) as the number of distinct subsequences of a (including the empty subsequence)…

D. Number of Parallelograms 题目连接: http://www.codeforces.com/contest/660/problem/D Description You are given n points on a plane. All the points are distinct and no three of them lie on the same line. Find the number of parallelograms with the vertice…

C. Hard Process 题目连接: http://www.codeforces.com/contest/660/problem/C Description You are given an array a with n elements. Each element of a is either 0 or 1. Let's denote the length of the longest subsegment of consecutive elements in a, consisting…