题目链接:http://codeforces.com/problemset/problem/702/A 题意: 给你N个数,a[0], a[1], a[2], ....., a[n-1],让你找出最长的连续上升子序列中元素的个数. 思路: 设dp[i]代表以a[i]结尾的连续上升子序列中元素的个数,那么dp[i] = (a[i] > a[i - 1] ? dp[i - 1] + 1 : 1),含义是如果a[i]比a[i-1]大,那么a[i]可以加入到以a[i-1]为尾的最长连续上升子序列末尾,取…

DP的学习计划,刷 https://codeforces.com/problemset?order=BY_RATING_ASC&tags=dp 遇到了这道题 https://codeforces.com/problemset/problem/702/A 以为是最长上升子序列(Longest Increasomg Subsequence)的模板题,发现自己不会做 记录一下大概的思路: \(O(n^2)\) 的算法: \(L[i]\) 选择 \(A[i]\) 为结尾的LIS的长度 \(P[i]\)…

简单$dp$. 如果$a[i]>a[i-1]$,那么$dp[i]=dp[i-1]+1$.否则,$dp[i]=1$.答案为$dp[i]$中的最大值. #pragma comment(linker, "/STACK:1024000000,1024000000") #include<cstdio> #include<cstring> #include<cmath> #include<algorithm> #include<vecto…

题目链接: A. Maximum Increase time limit per test 1 second memory limit per test 256 megabytes input standard input output standard output You are given array consisting of n integers. Your task is to find the maximum length of an increasing subarray of…

A. Maximum Increase time limit per test 1 second memory limit per test 256 megabytes input standard input output standard output You are given array consisting of n integers. Your task is to find the maximum length of an increasing subarray of the gi…

A. Maximum Increase time limit per test 1 second memory limit per test 256 megabytes input standard input output standard output You are given array consisting of n integers. Your task is to find the maximum length of an increasing subarray of the gi…

A. Maximum Increase time limit per test 1 second memory limit per test 256 megabytes input standard input output standard output You are given array consisting of n integers. Your task is to find the maximum length of an increasing subarray of the gi…

题目链接:Codeforces 484B Maximum Value 题目大意:给定一个序列,找到连个数ai和aj,ai%aj尽量大,而且ai≥aj 解题思路:类似于素数筛选法的方式,每次枚举aj,然后枚举k,每次用二分找到小于k∗aj而且最大的ai,维护答案,过程中加了一些剪枝. #include <cstdio> #include <cstring> #include <algorithm> using namespace std; const int maxn =…

题目描述: Maximum Value time limit per test 1 second memory limit per test 256 megabytes input standard input output standard output You are given a sequence a consisting of n integers. Find the maximum possible value of (integer remainder of *a**i* divi…

[Codeforces 1201D]Treasure Hunting(DP) 题面 有一个n*m的方格,方格上有k个宝藏,一个人从(1,1)出发,可以向左或者向右走,但不能向下走.给出q个列,在这些列上可以向上走,其他列不能向上走.可以重复经过同一个点.求从(1,1)出发,经过所有宝藏的最短路径长度 \(n,m,k,q \leq 2 \times 10^5\) 分析 贪心考虑,我们应该按照行一层一层的走.每一行应该从最左的宝藏走到最右的宝藏,或者从最右的宝藏走到最左的宝藏,然后找最近的一个可以向…

题目链接:900 E. Maximum Questions 题意: 给出一个长度为n只含有a和b还有'?'的串s,且'?'可以被任意替换为a或b.再给出一个字符串t (奇数位上为a,偶数位上为b,所以在题目中只给出了t的长度m),现在要求保证t在s中出现的次数最多的情况下面,使用'?'最小的情况使用了几个问号. 题解: 拿到这个题目可以看出是DP,但是比较难以解决的就是如何确定在第i个位置时前面m个字符能够满足t,这里我看了别人的题解 -.-哇,震惊!首先的话先对'?'做前缀和,然后设置两个数组…

题目链接:http://codeforces.com/contest/762/problem/D 多多分析状态:这个很明了 #include<bits/stdc++.h> using namespace std; #pragma comment(linker, "/STACK:102400000,102400000") #define ls i<<1 #define rs ls | 1 #define mid ((ll+rr)>>1) #define…

题目链接: http://codeforces.com/contest/889/problem/C 题意: 给你 \(n\)和 \(k\). 让你找一种全排列长度为\(n\)的 \(p\),满足存在下标 \(i\),\(p_i\)大于所有 \(p_j\),\(j\epsilon[1,i-1]\)同时大于所有\(p_i\),\(j\epsilon[i+1,i+k]\).问你满足这样条件的排列有多少种? 题解: 设\(dp[i]\)表示以 \(i\) 结尾的,满足题目要求的\(1\) ~ \(i\)…

题目链接: http://codeforces.com/contest/1249/problem/F 题意: 一棵树的每个节点有个权值,选择一个节点集,使得任意点对的距离大于$k$ 求最大节点集权值,节点集权值为节点集中节点权值和 数据范围: $1\leq n \leq 200$ $1\leq k \leq 200$ 分析: 定义$dp[v][i]$,代表在$v$这颗子树中,被选择的点最小深度恰好是$i$的最大答案 初始状态$dp[v][0]=a[v]$,这是没有子树的情况,然后再逐个添加子树…

<题目链接> 题目大意:给出一个01矩阵,行与行之间可以互换位置,问能够得到最大的全1矩阵的面积. #include <bits/stdc++.h> using namespace std; ; int n,m; int dp[N][N]; char mpa[N][N]; int main(){ while(~scanf("%d%d",&n,&m)){ ;i<=n;i++)scanf(); memset(dp,,sizeof(dp)); ;…

我们定义dp[ i ]表示长度为 i 的序列, 最后没有一个==k的时候返回的方案数, 也就是最后强制返回 i 的方案数. 我们能得到dp方程   dp[ i ] = sum(dp[ i - j - 1 ] * comb(i - 1,  j) * F[ j ])  0 <= j <= k - 1, 然后会发现这个东西不好转移, 我们可以把comb(i - 1,  j) * F[ j ] 这个东西合并一下变成 F(i - 1) / F(i - 1 - j) 然后就变成   dp[ i ] = F…

题目链接:http://codeforces.com/problemset/problem/332/B 题目大意:给你n个数和一个整数k,要求找到不相交的两个长度为k的区间,使得区间和最大,输出这两个区间的起点.解题思路:先计算前缀和,然后预处理出maxsum[i],maxsum[i]记录i~n最大的长度为k子段的和.然后再去枚举即可. #include<cstdio> #include<iostream> #include<algorithm> #include<…

题目链接  Maximum Element 题意  现在有这一段求序列中最大值的程度片段: (假定序列是一个1-n的排列) int fast_max(int n, int a[]) { int ans = 0; int offset = 0; for (int i = 0; i < n; ++i) if (ans < a[i]) { ans = a[i]; offset = 0; } else { offset = offset + 1; if (offset == k) return ans…

题意:给定 n 个数,问你连续的最长的序列是几个. 析:从头扫一遍即可. 代码如下: #include <cstdio> #include <string> #include <cstdlib> #include <cmath> #include <iostream> #include <cstring> #include <set> #include <queue> #include <algorith…

Maximum sum Time Limit: 1000MS   Memory Limit: 65536K Total Submissions: 39599   Accepted: 12370 Description Given a set of n integers: A={a1, a2,..., an}, we define a function d(A) as below: Your task is to calculate d(A). Input The input consists o…

http://www.codeforces.com/gym/100827/attachments Hill Number Time Limits:  5000 MS   Memory Limits:  200000 KB 64-bit interger IO format:  %lld   Java class name:  Main Description A Hill Number is a number whose digits possibly rise and then possibl…

题目链接: C. Journey time limit per test 3 seconds memory limit per test 256 megabytes input standard input output standard output Recently Irina arrived to one of the most famous cities of Berland — the Berlatov city. There are n showplaces in the city,…

题目链接: D. Kindergarten time limit per test 2 seconds memory limit per test 256 megabytes input standard input output standard output In a kindergarten, the children are being divided into groups. The teacher put the children in a line and associated e…

题目链接:http://codeforces.com/contest/332/problem/B 题意:在一个序列中,在所有长度为k的区间里找出两个不重叠的最大和,输出这两个最大和所对应的开头的位置a和b. 一开始没有想到用dp来做,于是有了以下的错误思路(读者可以忽略):声明一个结构体,包括head(保存起始点).tail(保存结束点)还有sum(保存长度为k的区间的和).计算出整个序列所有k个小区间的和sum,按sum从大到小排序(隐含的弊端:排序会导致区间与区间之间起始点和结束点的位置很不…

题目链接:http://codeforces.com/contest/710/problem/E 题意:开始文本为空,可以选择话费时间x输入或删除一个字符,也可以选择复制并粘贴一串字符(即长度变为两倍),问要获得长度为n的串所需最少的时间. 思路:dp[i]表示获得长度为i的串所需要的最短时间,分i为奇数和偶数讨论. #include<bits/stdc++.h> using namespace std; const int N=1e7+3; typedef long long ll; ll…

题目链接:http://codeforces.com/contest/699/problem/C dp[i][j]表示第i天做事情j所得到最小的假期,j=0,1,2. #include<bits/stdc++.h> using namespace std; const int INF=0x3f3f3f3f; int dp[105][3]; int main() { int n; scanf("%d",&n); memset(dp,INF,sizeof(dp)); d…

题目链接:http://codeforces.com/contest/706/problem/C #include<bits/stdc++.h> using namespace std; typedef long long ll; const int N=1e5+3; const ll INF=1e18; ll dp[N][2]; string a[N],b[N]; int c[N]; int main() { int n; scanf("%d",&n); for(…

Word Cut 题目连接: http://codeforces.com/problemset/problem/176/C Description Let's consider one interesting word game. In this game you should transform one word into another through special operations. Let's say we have word w, let's split this word in…

Boredom 题目链接: http://acm.hust.edu.cn/vjudge/contest/121334#problem/G Description Alex doesn't like boredom. That's why whenever he gets bored, he comes up with games. One long winter evening he came up with a game and decided to play it. Given a sequ…

http://codeforces.com/problemset/problem/148/D D. Bag of mice time limit per test 2 seconds memory limit per test 256 megabytes input standard input output standard output The dragon and the princess are arguing about what to do on the New Year's Eve…