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#include <iostream>
#include <algorithm>
#include <vector>
#include <fstream>
#include <limits>
#include <queue>
using namespace std;
ifstream fin("maxflow.in");
ofstream fout("maxflow.out");
struct Edge
{
int v, u;
long long cap, flow = 0;
Edge(int v, int u, long long cap)
{
this->v = v;
this->u = u;
this->cap = cap;
}
};
struct Dinic
{
long long const inf_flow = numeric_limits<long long>::max();
vector<Edge> edges;
vector<vector<int>> adjList;
int n, m = 0;
int s, t;
vector<int> level, ptr;
queue<int> q;
explicit Dinic(int n, int s, int t)
{
this->n = n;
this->s = s;
this->t = t;
adjList.resize(n);
level.resize(n);
ptr.resize(n);
}
void add_edge(int v, int u, long long capacity)
{
edges.emplace_back(v, u, capacity);
edges.emplace_back(u, v, 0);
adjList[v].push_back(m);
adjList[u].push_back(m + 1);
m += 2;
}
bool bfs()
{
while (q.empty() == false)
{
int v = q.front();
q.pop();
for (auto id : adjList[v])
{
if (edges[id].cap - edges[id].flow < 1)
continue;
if (level[edges[id].u] != -1)
continue;
level[edges[id].u] = level[v] + 1;
q.push(edges[id].u);
}
}
return level[t] != -1;
}
long long dfs(int v, long long pushed)
{
if (pushed == 0)
return 0;
if (v == t)
return pushed;
int siz = static_cast<int>(adjList[v].size());
for (int &cid = ptr[v]; cid < siz; cid++)
{
int id = adjList[v][cid];
int u = edges[id].u;
if (level[v] + 1 != level[u] || edges[id].cap - edges[id].flow < 1)
continue;
long long tr = dfs(u, min(pushed, edges[id].cap - edges[id].flow));
if (tr == 0)
continue;
edges[id].flow += tr;
edges[id ^ 1].flow -= tr;
return tr;
}
return 0;
}
long long flow()
{
long long f = 0;
while (true)
{
fill(level.begin(), level.end(), -1);
level[s] = 0;
q.push(s);
if (!bfs())
break;
fill(ptr.begin(), ptr.end(), 0);
while (long long pushed = dfs(s, inf_flow))
f += pushed;
}
return f;
}
};
int main()
{
int n, m;
fin >> n >> m;
Dinic solve(n + 1, 1, n);
for (int i = 0; i < m; i++)
{
int x, y, z;
fin >> x >> y >> z;
solve.add_edge(x, y, z);
}
fout << solve.flow();
return 0;
}