电波 #include<bits/stdc++.h> using namespace std; #define LL long long #define maxn 30000 vector<int>q[maxn]; int dfn[maxn],low[maxn],st[maxn],vis[maxn],top; int num[maxn],i; void dfs(int u,int deep,int fa){ dfn[u]=deep; low[u]=deep; st[++top]=u…
推荐博客 :https://blog.csdn.net/qq_25576697/article/details/81138213 链接:https://www.nowcoder.com/acm/contest/139/A来源:牛客网 题目描述Count the number of n x m matrices A satisfying the following condition modulo (109+7).* Ai, j ∈ {0, 1, 2} for all 1 ≤ i ≤ n, 1 ≤…