POI1119

/*
* this code is made by LinMeiChen
* Problem:
* Type of Problem:
* Thinking:
* Feeling:
*/
#include<iostream>
#include<algorithm>
#include<stdlib.h>
#include<string.h>
#include<stdio.h>
#include<math.h>
#include<string>
#include<vector>
#include<queue>
#include<list>
using namespace std;
typedef long long lld;
typedef unsigned int ud;
#define oo 0x3f3f3f3f
#define maxn 1010
int map[maxn][maxn];
int dfn[maxn], mark[maxn];
int low[maxn], subnets[maxn];
int nodes, g_dfn, s, son;


void DFS(int u)
{
mark[u] = 1;
for (int v = 1; v <= nodes; v++)
{
if (map[u][v])
{
if (!mark[v])
{
low[v] = dfn[v] = ++g_dfn;
DFS(v);
low[u] = min(low[v], low[u]);
if (low[v] >= dfn[u])
{
if (u == s)
son++;
else
subnets[u]++;
}
}
else
low[u] = min(low[u], dfn[v]);
}
}
}


int main()
{
int u, v;
s = 1;
for (int cas = 1;true;cas++)
{
memset(map, 0, sizeof map);
memset(subnets, 0, sizeof subnets);
memset(mark, 0, sizeof mark);
memset(low, 0, sizeof low);
memset(dfn, 0, sizeof dfn);
low[s] = dfn[s] = 1;
g_dfn = 1;
nodes = 0;
son = 0;


scanf("%d", &u);
if (u == 0)
break;
scanf("%d", &v);
map[u][v] = map[v][u] = 1;
nodes = max(max(nodes, u), v);
while (true)
{
scanf("%d", &u);
if (u == 0)
break;
scanf("%d", &v);
map[u][v] = map[v][u] = 1;
nodes = max(max(nodes, u), v);
}


DFS(s);


if (cas > 1)
puts("");
printf("Network #%d\n", cas);
if (son > 1)
subnets[s] = son - 1;
bool find = false;
for (int i = 1; i <= nodes; i++)
{
if (subnets[i])
{
printf("  SPF node %d leaves %d subnets\n", i, subnets[i] + 1);
find = true;
}
}
if (!find)
printf("  No SPF nodes\n");
}
return 0;
}