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#include <algorithm>
#include <iostream>
#include <list>
#include "sabotaz.h"
#include "message.h"
using namespace std;
 
class Graph
{
    long V;
    list<long> *adj;
    list<long> *adjRepeated; 
    long bridgeUtil(long v, bool visited[], long disc[], long low[], long parent[], long start, long end);
public:
    Graph(long V);
    void addEdge(long v, long w); 
    long bridge(long start, long end);
};
 
Graph::Graph(long V)
{
    this->V = V;
    adj = new list<long>[V];
	adjRepeated = new list<long>[V];
}
 
void Graph::addEdge(long v, long w)
{
	list<long>::iterator findIter = find(adj[v].begin(), adj[v].end(), w);	
	if(adj[v].end() == findIter) //edge does not already exist
	{		
		adj[v].push_back(w);
		adj[w].push_back(v);  
	}
	else //already exists
	{
		adjRepeated[v].push_back(w);
		adjRepeated[w].push_back(v); 
	}
		
}
 
long Graph::bridgeUtil(long u, bool visited[], long disc[], 
                                       long low[], long parent[], long start, long end)
{
    static long time = 0;
	long bridges = 0;
  
    visited[u] = true;
 
    disc[u] = low[u] = ++time;
 

    list<long>::iterator i;
    for (i = adj[u].begin(); i != adj[u].end(); ++i)
    {
        long v = *i;  
 
        if (!visited[v])
        {
            parent[v] = u;
            bridges += bridgeUtil(v, visited, disc, low, parent, start, end);
 
            low[u]  = min(low[u], low[v]);
 
            if (low[v] > disc[u]){
			   list<long>::iterator findIter = find(adjRepeated[v].begin(), adjRepeated[v].end(), u);
			   if(findIter == adjRepeated[v].end()){								   			  
			  
					  if(u >= start && v >= start && u<=end && v <=end){ //both in scope, ok
							bridges++;
					  }
					  else{ //one in scope, count only if smaller is in scope
							if( u < v){
								if(u >= start && u<=end){
									bridges++;
								}
							}
							else{
								if(v >= start && v<=end){
									bridges++;
								}
							}
					  }
				}
			}
        }
        else if (v != parent[u])
            low[u]  = min(low[u], disc[v]);
    }
	return bridges;
}
 
long Graph::bridge(long start, long end)
{
    bool *visited = new bool[V];
    long *disc = new long[V];
    long *low = new long[V];
    long *parent = new long[V];
 
    for (long i = 0; i < V; i++)
    {
        parent[i] = -1;
        visited[i] = false;
    }
 
	long bridges = 0;
    for (long i = 0; i < V; i++){
        if (visited[i] == false){
            bridges += bridgeUtil(i, visited, disc, low, parent, start, end);
		}
	}
	return bridges;
}
 
int main()
{    
	Graph g(NumberOfIsles());
	long bridges = NumberOfBridges();
	for(long i=0; i<bridges; i++){
		if(BridgeEndA(i) != BridgeEndB(i)){
			g.addEdge(BridgeEndA(i), BridgeEndB(i));
		}
	}
	
	if(NumberOfIsles() < NumberOfNodes() || NumberOfNodes() == 1){
		if(MyNodeId()==0){
			cout<<g.bridge(0, NumberOfIsles()-1)<<endl;
		}
	}
	else{
		long oneInstanceScope = (long)(NumberOfIsles()/NumberOfNodes());
		long myStartIndex = MyNodeId() * oneInstanceScope;
		long myEndIndex = myStartIndex + oneInstanceScope - 1;
		if(MyNodeId() == NumberOfNodes() - 1){
			myEndIndex = NumberOfIsles()-1;
		}
		long bridges = g.bridge(myStartIndex, myEndIndex);
		if(MyNodeId()==0){
			for(long i=1; i < NumberOfNodes(); i++){
				Receive(i);
				bridges += GetInt(i);
			}
			cout<<bridges<<endl;	
		}
		else{
			PutInt(0, bridges);
			Send(0);
		}	
	}
    return 0;
}