题目链接:http://acm.csu.edu.cn/csuoj/problemset/problem?pid=1809 Bobo has a balanced parenthesis sequence P=p 1 p 2…p n of length n and q questions. The i-th question is whether P remains balanced after p ai and p bi swapped. Note that questions are ind…
Country of Metropolia is holding Olympiad of Metrpolises soon. It mean that all jury members of the olympiad should meet together in Metropolis (the capital of the country) for the problem preparation process. There are n + 1 cities consecutively num…
题目: http://acm.hdu.edu.cn/showproblem.php?pid=4312 Meeting point-2 Time Limit: 2000/1000 MS (Java/Others) Memory Limit: 32768/32768 K (Java/Others)Total Submission(s): 1231 Accepted Submission(s): 691 Problem Description It has been ten years s…
只需不断维护相对值的前缀就能得到解 这种思想第一次是在树状数组区间更新那里看到的,由于题目要求是1~n所以直接可以用前缀和维护 注意不能直接-1 +1 还有POJ的数据..要不是书里有提谁知道会这么毒瘤 /*H E A D*/ int delta[maxn]; map<P,int> vis; int main(){ int n,I,h,r,a,b; while(~iin(n)){ I=read();h=read();r=read(); memset(delta,0,sizeof delta);…
题目链接 Hiho 1496 设$f[i]$为二进制集合包含$i$的最大的两个数,这个东西用高维前缀和维护. 高位前缀和转移的具体方案 :枚举每一位,然后枚举每个集合,大的转移到小的. 注意合并的时候最好别用$std::sort$(我一开始被卡常数了) #include <bits/stdc++.h> using namespace std; #define rep(i, a, b) for (int i(a); i <= (b); ++i) #define dec(i, a, b)…
B. Segment Occurrences time limit per test 2 seconds memory limit per test 256 megabytes input standard input output standard output You are given two strings s and t , both consisting only of lowercase Latin letters. The substring s[l..r] is the str…
B. Balanced Substring You are given a string s consisting only of characters 0 and 1. A substring [l, r] of s is a string slsl + 1sl + 2... sr, and its length equals to r - l + 1. A substring is called balanced if the number of zeroes (0) equals to t…
题目大意: 两个人玩取数游戏,第一个人分数一开始是a,第二个分数一开始是b,接下来t轮,每轮两人都选择一个[-k,k]范围内的整数,加到自己的分数里,求有多少种情况使得t轮结束后a的分数比b高. (1 ≤ a, b ≤ 100, 1 ≤ k ≤ 1000, 1 ≤ t ≤ 100) 1.我一开始的想法是DP出玩i轮得分是j的方案数.然后状态数最多有t*(2*k*t)那么多,最坏情况下会有2e7那么多的状态,转移必须是O(1)的. dp[i][j]=sum(dp[i-1][j-k....j+k]…
