ZOJ 3811 zoj 3811 Untrusted Patrol牡丹江网络赛C题

去年的比赛题目,今年才搞懂AC了＝＝＝||

  1 #include <cstdio>
  2 #include <cstdlib>
  3 #include <cstring>
  4 #include <cctype>
  5 #include <cmath>
  6 #include <algorithm>
  7 #include <vector>
  8 #include <queue>
  9 #include <stack>
 10 using namespace std;
 11
 12 const int inf = 0x3f;
 13 const int INF = 0x3f3f3f3f;
 14 const int maxn = 100005;
 15 int N, M, K, L;
 16 bool sen[maxn], visit[maxn];
 17 int pass[maxn];
 18 int f[maxn];
 19 vector <int>G[maxn];
 20 queue <int> q;
 21
 22 int find(int x)
 23 {
 24     return x == f[x] ? x : f[x] = find(f[x]);
 25 }
 26 void Union(int x, int y)
 27 {
 28     int fx = find(x), fy = find(y);
 29
 30     if (fx == fy)
 31     {
 32         return ;
 33     }
 34
 35     if (fx > fy)
 36     {
 37         swap(fx, fy);
 38     }
 39
 40     f[fx] = fy;
 41 }
 42
 43 bool BFS(int start)
 44 {
 45     while (!q.empty())
 46     {
 47         q.pop();
 48     }
 49
 50     q.push(start);
 51
 52     visit[start] = true;
 53
 54     while (!q.empty())
 55     {
 56         int now, next;
 57         now = q.front();
 58         q.pop();
 59
 60         for (int i = 0; i < G[now].size(); i++)
 61         {
 62             next = G[now][i];
 63
 64             //printf("start = %d, next = %d\n", start, next);
 65             if (visit[next])
 66             {
 67                 continue;
 68             }
 69
 70             visit[next] = true;
 71             //如果是传感器不会入队列,但是要标记为 访问过
 72             if (sen[next])
 73             {
 74                 continue;
 75             }
 76             q.push(next);
 77         }
 78     }
 79
 80     return false;
 81 }
 82
 83 bool slove()
 84 {
 85     if(K == 0) return true;
 86     if(K != L) return false;
 87
 88     for (int i = 0; i < L - 1; i++)
 89     {
 90         BFS(pass[i]);
 91         if(!visit[pass[i+1]]) return false;
 92     }
 93     BFS(pass[L-1]);
 94
 95     for(int i = 1; i <= N; i++) //检查所有点是否都被访问了
 96         if(!visit[i])
 97             return false;
 98     return true;
 99
100 }
101 int main()
102 {
103     int t;
104     scanf("%d", &t);
105
106     while (t--)
107     {
108         memset(sen, false, sizeof(sen));
109         memset(visit, false, sizeof(visit));
110
111         int x, y, f = 0;
112         scanf("%d %d %d", &N, &M, &K);
113
114         for(int i = 1; i <= N; i++)
115             G[i].clear(); //千万不要忘记清空啊
116
117         for (int i = 0; i < K; i++)
118         {
119             scanf("%d", &x);
120             sen[x] = true;
121         }
122
123         for (int i = 0; i < M; i++)
124         {
125             scanf("%d %d", &x, &y);
126             G[x].push_back(y);
127             G[y].push_back(x);
128         }
129
130         scanf("%d", &L);
131
132         for (int i = 0; i < L; i++)
133         {
134             scanf("%d", &pass[i]);
135         }
136
137
138         if (!slove())
139         {
140             puts("No");
141         }
142         else
143         {
144             puts("Yes");
145         }
146     }
147 }