Rikka with Graph Time Limit: 2000/1000 MS (Java/Others)    Memory Limit: 65536/65536 K (Java/Others) Problem Description As we know, Rikka is poor at math. Yuta is worrying about this situation, so he gives Rikka some math tasks to practice. There is…

Rikka with Graph 思路: 官方题解: 代码: #include<bits/stdc++.h> using namespace std; #define ll long long int main() { int t; scanf("%d",&t); while(t--) { ll n,m,ans; scanf("%lld%lld",&n,&m); ) { ans=m*+(m-)*m*+(n*(n-)-m*-(m-)…

Rikka with Graph 题目连接: http://acm.hdu.edu.cn/showproblem.php?pid=5631 Description As we know, Rikka is poor at math. Yuta is worrying about this situation, so he gives Rikka some math tasks to practice. There is one of them: Yuta has a non-direct gra…

思路来自 某FXXL 不过复杂度咋算的.. /* HDU 6091 - Rikka with Match [ 树形DP ] | 2017 Multi-University Training Contest 5 题意: 给出N个点的树,求去边的方案数使得 去边后最大匹配数是M的倍数 限制: N<=5e4, M<=200 分析: 设 DP[u][i][0] 表示 以点 u 为根的子树 最大匹配数模 m 为 i 时,且 u 点没有匹配的方案数 DP[u][i][1] 表示 以点 u 为根的子树 最大…

思路和任意模数FFT模板都来自 这里 看了一晚上那篇<再探快速傅里叶变换>还是懵得不行,可能水平还没到- - 只能先存个模板了,这题单模数NTT跑了5.9s,没敢写三模数NTT,可能姿势太差了... 具体推导大概这样就可以了: /* HDU 6088 - Rikka with Rock-paper-scissors [ 任意模数FFT,数论 ] | 2017 Multi-University Training Contest 5 题意: 计算 3^n * ∑ [0<=i+j<=n]…

JAVA+大数搞了一遍- - 不是很麻烦- - /* HDU 6093 - Rikka with Number [ 进制转换,康托展开,大数 ] | 2017 Multi-University Training Contest 5 题意: 求L,R之间的好数的个数,好数要求在某个d(>=2)进制下数位是0到d-1的 分析: d 进制下好数的个数为 d!-(d-1)! ,且满足 d^(d-1) <= K <= d^d 可知 若 N > d^d 则 1-N 包含前 d-1 个进制的所有…

看了标程的压位,才知道压位也能很容易写- - /* HDU 6085 - Rikka with Candies [ 压位 ] | 2017 Multi-University Training Contest 5 题意: 给定 A[N], B[N], Q 个 k 对于每个k, 求 A[i] % B[j] == k 的 (i,j)对数 限制 N, Q <=50000 分析: 对于每个 B[i] 按其倍数分块,则对于 A[j] ∈ [x*B[i],(x+1)*B[i]) , A[j]%B[i] = A…

Rikka with Graph Time Limit: 2000/1000 MS (Java/Others)    Memory Limit: 65536/65536 K (Java/Others) Total Submission(s): 182    Accepted Submission(s): 95 Problem Description As we know, Rikka is poor at math. Yuta is worrying about this situation,…

Rikka with Graph II Time Limit: 2000/1000 MS (Java/Others)    Memory Limit: 65536/65536 K (Java/Others)Total Submission(s): 1051    Accepted Submission(s): 266 Problem Description As we know, Rikka is poor at math. Yuta is worrying about this situati…

/* HDU 6162 - Ch’s gift [ LCA,线段树 ] | 2017 ZJUT Multi-University Training 9 题意: N节点的树,Q组询问 每次询问s,t两节点之间的路径上点权值在[a,b]之间的点权总和 分析: 求出每个询问的LCA,然后离线 按dfs顺序更新树状数组,即某点处树状数组中存的值为其所有祖先节点的值 每个点处对答案的贡献为: 当其为第 i 个 lca 时, ans[i] -= 2 * query(a,b) , 再特判该节点 当其为第 i…