Zoj 1119

#include <iostream>#include <cstring>using namespace std;#define min(a, b) (a < b ? a : b)int Edge[1001][1001];int visited[1001];int low[1001];int dfn[1001];int nodes;int tmpdfn;int subnets[1001];int sons;void DFS( int u ){for(int v = 1; v <= nodes; ++v){if(Edge[u][v]){if(!visited[v]){visited[v] = 1;tmpdfn++;low[v] = dfn[v] = tmpdfn;DFS( v );low[u] = min(low[u], low[v]);if(low[v] >= dfn[u]){if(u != 1)subnets[u]++;if(u == 1)sons++;}}elselow[u] = min(low[u], dfn[v]);}}}void inite(){sons = 0;tmpdfn = 1;low[1] = dfn[1] = 1;memset( visited, 0, sizeof(visited));visited[1] = 1;memset( subnets, 0, sizeof(subnets));}int main(){int i;int u, v;int kfind;int number = 1;while( 1 ){cin>>u;if(u == 0)break;memset(Edge, 0, sizeof(Edge));nodes = 0;cin>>v;if(nodes < u)nodes = u;if(nodes < v)nodes = v;Edge[u][v] = Edge[v][u] = 1;while(1){cin>>u;if(u == 0)break;cin>>v;if(u > nodes)nodes = u;if(v > nodes)nodes = v;Edge[u][v] = Edge[v][u] = 1;}if(number > 1)cout<<endl;cout<<"Network #"<<number<<endl;number++;inite();DFS( 1 );if(sons > 1)subnets[1] = sons - 1;kfind = 0;for(i = 1; i <= nodes; ++i){if(subnets[i]){kfind = 1;cout<<"  SPF node "<<i<<" leaves "<<subnets[i] + 1<<" subnets"<<endl;}}if( !kfind ){cout<<"  No SPF nodes"<<endl;}}return 0;}