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

#include <algorithm>
#include <iostream>
#include <vector>

using namespace std;

const int N = 200001;
vector<pair<int, bool> > g[N];
int d[N];
int low[N];
int par[N];
int n, m;

void clear()
{
    for(int i = 1; i <= n; i++)
    {
	g[i].clear();
	d[i] = low[i] = 0;
    }
}

void buildGraph(const vector<int> &father)
{
    for(int i = 0; i < n; i++)
	if(father[i] < 0)
	{
	    g[i+1].emplace_back(-father[i], true);
	    g[-father[i]].emplace_back(i+1, true);
	}
	else if(father[i] > 0)
	{
	    g[i+1].emplace_back(father[i], false);
	    g[father[i]].emplace_back(i+1, false);
	}
}

void dfs(int v, int prev)
{
    low[v] = d[v] = d[prev] + 1;
    par[v] = prev;
    bool firstPrev = true;
    for(auto u: g[v])
	if(u.first == prev && firstPrev && !u.second)
	    firstPrev = false;
	else if(d[u.first]) low[v] = min(low[v], d[u.first]);
	else
	{
	    dfs(u.first, v);
	    low[v] = min(low[v], low[u.first]);
	}
}

vector<int> solve()
{
    for(int i = 1; i <= n; i++)
	if(!d[i]) dfs(i, 0);
    vector<int> ans;
    ans.reserve(n);
    for(int i = 1; i <= n; i++)
	if(low[i] == d[i]) ans.push_back(par[i]);
	else ans.push_back(-par[i]);
    return ans;
}

const int MAXSIZE = 20000;

void send(const vector<int> &vec, int target)
{
    
    for(int i = 0; i < n; i += MAXSIZE)
    {
	for(int j = 0; j < MAXSIZE && i + j < n; j++)
	    PutInt(target, vec[i+j]);
	Send(target);
    }
}

vector<int> receive(int target)
{
    vector<int> ans(n);
    for(int i = 0; i < n; i += MAXSIZE)
    {
	Receive(target);
	for(int j = 0; j < MAXSIZE && i + j < n; j++)
	    ans[i+j] = GetInt(target);
    }
    return ans;
}

int main() 
{
    n = NumberOfIsles();
    m = NumberOfBridges();
    int nodes = NumberOfNodes(), id = MyNodeId();
    int block = (m + nodes - 1) / nodes;
    int start = id * block;
    for(int i = start; i < start + block && i < m; i++)
    {
	int a = BridgeEndA(i) + 1, b = BridgeEndB(i) + 1;
	g[a].emplace_back(b, false);
	g[b].emplace_back(a, false);
    }
    auto vec = solve();
    int k = 1;
    while(true)
    {
	int s = id ^ k;
	if(s < id)
	{
	    send(vec, s);
	    return 0;
	}
	if(s < nodes)
	{
	    auto vec2 = receive(s);
	    clear();
	    buildGraph(vec);
	    buildGraph(vec2);
	    vec = solve();
	}
	else if(id == 0)
	{
	    int ans = 0;
	    for(int x: vec)
		if(x > 0) ans++;
	    printf("%d\n", ans);
	    return 0;
	}
	k <<= 1;
    }
}