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#include <bits/stdc++.h>

#include "message.h"
#include "sabotaz.h"

#define REP(a,b) for(int a=0; a<(b); ++a)
#define FWD(a,b,c) for(int a=(b); a<(c); ++a)
#define FWDS(a,b,c,d) for(int a=(b); a<(c); a+=d)
#define BCK(a,b,c) for(int a=(b); a>(c); --a)
#define ALL(a) (a).begin(), (a).end()
#define SIZE(a) ((int)(a).size())
#define SQ(a) ((a)*(a))
#define VAR(x) #x ": " << x << " "
#define popcount __builtin_popcount
#define popcountll __builtin_popcountll
#define gcd __gcd
#define x first
#define y second
#define st first
#define nd second
#define pb push_back

using namespace std;

template<typename T> ostream& operator<<(ostream &out, const vector<T> &v){ out << "{"; for(const T &a : v) out << a << ", "; out << "}"; return out; }
template<typename S, typename T> ostream& operator<<(ostream &out, const pair<S,T> &p){ out << "(" << p.st << ", " << p.nd << ")"; return out; }

typedef long long int64;
typedef pair<int, int> PII;
typedef pair<int64, int64> PLL;
typedef long double K;
typedef vector<int> VI;

const int dx[] = {0,0,-1,1}; //1,1,-1,1};
const int dy[] = {-1,1,0,0}; //1,-1,1,-1};

const int64 INF = SQ(1000LL * 1000 * 1000);

int instance;
int instance_count;

int n, t;
vector<PII> edges;
int bridges;

vector<int> out[200010];
int pre[200010];
vector<int> st;

int dfs(int u, int p){
	int q = p;
	pre[u] = ++t;
	int low = t;

	int block = SIZE(st);
	st.push_back(u);

	for(int v : out[u]){
		if(pre[v]){
			if(p == v)
				p = -1;
			else
				low = min(low, pre[v]);
		}else{
			low = min(low, dfs(v, u));
		}
	}
	if(low == pre[u]){
		if(block + 1 < SIZE(st)){
			edges.push_back(PII(st[block], st.back()));
			FWD(i,block,SIZE(st)-1) edges.push_back(PII(st[i], st[i+1]));
		}
		st.resize(block);
		if(q != -1){
			edges.push_back(PII(u, q));
			++bridges;
		}
	}
	return low;
}

void reduce(){
	bridges = 0;
	FWD(i,0,n) pre[i] = 0, out[i].clear();

	for(PII e : edges){
		out[e.st].push_back(e.nd);
		out[e.nd].push_back(e.st);
	}
	edges.clear();

	t = 0;
	FWD(i,0,n) if(!pre[i]) dfs(i, -1);
}

void send_edges(int target){
	PutInt(target, SIZE(edges));
	Send(target);
	FWD(i,0,SIZE(edges)){
		PutInt(target, edges[i].st);
		PutInt(target, edges[i].nd);
		if(i+1 == SIZE(edges) || (i+1)%30000 == 0)
			Send(target);
	}
}

void receive_edges(int source){
	Receive(source);
	int k = GetInt(source);
	FWD(i,0,k){
		if(i % 30000 == 0)
			Receive(source);
		edges.push_back(PII(GetInt(source), GetInt(source)));
	}
}

int main(){
	instance = MyNodeId();
	instance_count = NumberOfNodes();

	n = NumberOfIsles();

	int m = NumberOfBridges();
	int a = (int)((int64)m * instance / instance_count);
	int b = (int)((int64)m * (instance+1) / instance_count);

	FWD(i,a,b) edges.push_back(PII(BridgeEndA(i), BridgeEndB(i)));

	reduce();

	int s = sqrt(instance_count);

	if(instance < s){
		FWD(source,s,instance_count)
			if(source % s == instance)
				receive_edges(source);
	}else{
		send_edges(instance % s);
		return 0;
	}

	reduce();

	if(instance < 1){
		FWD(source,1,s)
			receive_edges(source);
	}else{
		send_edges(0);
		return 0;
	}

	reduce();

	printf("%d\n", bridges);
	return 0;
}