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#include <iostream>
#include <fstream>
#include <list>
std::ifstream fin{ "maxflow.in" };
std::ofstream fout{ "maxflow.out" };
const int oo = int(1e9);
const int N_MAX = 1000 + 1;
const int M_NAX = 5000 + 1;
int N, M;
int s, t;
int capacity[N_MAX][N_MAX];
int preflow[N_MAX][N_MAX];
int excess[N_MAX];
int height[N_MAX];
int next[N_MAX];
std::list<int> L;
void relabel(int u)
{
int min_height = oo;
for (int v = 1; v <= N; ++v)
{
if (preflow[u][v] < capacity[u][v] && height[u] <= height[v])
{
min_height = std::min(min_height, height[v]);
}
}
height[u] = min_height + 1;
}
void push(int u, int v)
{
int delta = std::min(excess[u], capacity[u][v] - preflow[u][v]);
preflow[u][v] += delta;
preflow[v][u] -= delta;
excess[u] -= delta;
excess[v] += delta;
}
void discharge(int u)
{
while (excess[u] > 0)
{
if (next[u] > N)
{
relabel(u);
next[u] = 1;
}
if (preflow[u][next[u]] < capacity[u][next[u]] && height[u] == height[next[u]] + 1)
{
push(u, next[u]);
}
else
{
++next[u];
}
}
}
int main()
{
fin >> N >> M;
s = 1;
excess[s] = oo;
height[s] = N;
t = N;
for (int i = 1; i <= M; ++i)
{
int u, v, c;
fin >> u >> v >> c;
capacity[u][v] = c;
if (s == u)
{
push(s, v);
}
}
for (int u = 1; u <= N; ++u)
{
next[u] = 1;
if (u != s && u != t)
{
L.push_back(u);
}
}
auto it = L.begin();
while (it != L.end())
{
int u = *it;
int old_height = height[u];
discharge(u);
if (old_height != height[u])
{
L.erase(it);
L.push_front(u);
it = L.begin();
}
++it;
}
fout << excess[t];
}