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#include<fstream>
#include<vector>
#include<queue>
#include<algorithm>
using namespace std;
ifstream fin("maxflow.in");
ofstream fout("maxflow.out");
class Graph
{
private:
const int INF = 1 << 30;
struct muchie
{
int to,ind,flow,cap;
};
vector<vector<muchie>> vecini;
vector<int> dist,rem;
int n,s,t;
bool bfs()
{
fill(dist.begin(),dist.end(),INF);
dist[s] = 0;
queue<int> q; q.push(s);
while(!q.empty())
{
int v = q.front(); q.pop();
for(auto &it : vecini[v])
{
if(it.cap <= it.flow || dist[it.to] != INF) continue;
dist[it.to] = dist[v] + 1;
q.push(it.to);
}
}
return (dist[t] != INF);
}
int dfs(int nod,int f)
{
if(nod == t) return f;
for(int &h = rem[nod] ; h < vecini[nod].size() ; h++)
{
muchie &care = vecini[nod][h];
if(dist[nod] + 1 != dist[care.to] || care.flow >= care.cap) continue;
int exp = dfs(care.to,min(f,care.cap - care.flow));
if(exp)
{
care.flow += exp;
vecini[care.to][care.ind].flow -= exp;
return exp;
}
}
return 0;
}
public :
Graph(int _n,int _s,int _t)
{
vecini.resize(n + 1);
dist.resize(n + 1);
rem.resize(n + 1);
n = _n,s = _s,t = _t;
}
void add(int a,int b,int c)
{
vecini[a].push_back({b,vecini[b].size(),0,c});
vecini[b].push_back({a,vecini[a].size() - 1,0,0});
}
int maxflow()
{
int ans = 0;
while(bfs())
{
fill(rem.begin(),rem.end(),0);
int delta = dfs(s,INF);
while(delta > 0)
{
ans += delta;
delta = dfs(s,INF);
}
}
return ans;
}
};
int main()
{
int n,m,a,b,c; fin >> n >> m;
Graph graph(n,1,n);
while(m--)
{
fin >> a >> b >> c;
graph.add(a,b,c);
}
fout << graph.maxflow();
}