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#include <iostream>
#include <fstream>
#include <vector>
#include <deque>
const int oo = int(1e9);
const int N_MAX = 1000 + 1;
const int M_NAX = 5000 + 1;
struct Edge {
int capacity{ 0 };
int preflow{ 0 };
bool exists{ false };
};
int N, M;
Edge graph[N_MAX][N_MAX];
int excess[N_MAX];
int height[N_MAX];
int next[N_MAX];
void relabel(int u)
{
int min_height = oo;
for (int v = 1; v <= N; ++v)
{
if (graph[u][v].preflow < graph[u][v].capacity && 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], graph[u][v].capacity - graph[u][v].preflow);
graph[u][v].preflow += delta;
graph[v][u].preflow -= 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 (graph[u][next[u]].preflow < graph[u][next[u]].capacity && height[u] == height[next[u]] + 1)
{
push(u, next[u]);
}
else
{
++next[u];
}
}
}
int main()
{
std::ifstream fin{ "maxflow.in" };
std::ofstream fout{ "maxflow.out" };
fin >> N >> M;
for (int i = 1; i <= M; ++i)
{
int u, v, c;
fin >> u >> v >> c;
graph[u][v].capacity = c;
graph[u][v].exists = true;
graph[v][u].exists = true;
}
int s = 1, t = N;
height[s] = N;
excess[s] = oo;
for (int u = 1; u <= N; ++u)
{
if (graph[s][u].exists == true)
{
push(s, u);
}
next[u] = 1;
}
std::vector<int> L;
for (int u = 1; u <= N; ++u)
{
if (u == s || u == t) continue;
L.push_back(u);
}
int pos = 0;
while (pos < L.size())
{
int u = L[pos];
int old_height = height[u];
discharge(u);
if (old_height != height[u])
{
L.erase(L.begin() + pos);
L.insert(L.begin(), u);
pos = 0;
}
++pos;
}
fout << excess[t] << std::endl;
}