HDU-3018 Ant Trip（欧拉回路） 

 1 #include <bits/stdc++.h>
 2 #define _for(i,a,b) for(int i = (a);i < (b);i ++)
 3 using namespace std;
 4 
 5 const int MAXV = 100003;
 6 int V,E,Vis[MAXV];
 7 vector<int> G[MAXV];
 8 
 9 int dfs(int u)
10 {
11     if(Vis[u]) return 0;
12     Vis[u] = 1;
13     int sz = G[u].size(),r = sz&0x1;
14     _for(i,0,sz) r += dfs(G[u][i]);
15     return r;
16 }
17 
18 int main()
19 {
20     for(int a,b,n;cin >> V >> E;n = 0)
21     {
22         _for(i,0,V+1) G[i].clear();
23         memset(Vis,0,sizeof(Vis));
24         _for(i,0,E)
25         {
26             cin >> a >> b;
27             if(a==b) continue;
28             G[a-1].push_back(b-1),G[b-1].push_back(a-1);
29         }
30 
31         _for(i,0,V)
32         {
33             if(Vis[i] || G[i].empty())    continue;
34             n ++,n += max(0,dfs(i)/2-1);
35         }
36         cout << n << endl;
37     }
38     return 0;
39 }

 

posted @ 2018-11-28 21:24  Asurudo  阅读(137)  评论(0)    收藏  举报