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#include <fstream>
#include <unordered_set>
#include <iostream>
#include <limits.h>
#include <string.h>
#include <queue>
#include <map>
#include <vector>
#define MAX 999999
using namespace std;
int c[1000][1000], mflow[1000][1000];
map<int, unordered_set<int>> nodes;
int main()
{
memset(c, 0, sizeof(c));
ifstream in;
in.open("maxflow.in", ios::in);
int n, m, u, v, source, dest;
in >> n >> m;
source = 0;
dest = n - 1;
for (int i = 0; i < m; i++)
{
in >> u >> v;
u--;
v--;
nodes[u].insert(v);
nodes[v].insert(u);
in >> c[u][v];
}
in.close();
unordered_set<int> visited;
int parent[1000];
long max_flow = 0;
for (;;)
{
memset(parent, 0, sizeof(parent));
parent[source] = -1;
visited.clear();
visited.insert(source);
queue<int> q;
q.push(source);
while (!q.empty())
{
int nod = q.front();
q.pop();
for (unordered_set<int>::const_iterator it = nodes[nod].begin(); it != nodes[nod].end(); it++)
{
if (visited.find(*it) == visited.end() && c[nod][*it] - mflow[nod][*it] > 0)
{
visited.insert(*it);
if (*it != dest)
{
q.push(*it);
parent[*it] = nod;
}
}
}
}
if (visited.find(dest) == visited.end())
break;
for(unordered_set<int>::const_iterator it = nodes[dest].begin(); it != nodes[dest].end(); it++)
if (visited.find(*it) != visited.end() && c[*it][dest] - mflow[*it][dest] > 0)
{
int min_f = MAX;
parent[dest] = *it;
for (v = dest; v != source; v = parent[v])
{
u = parent[v];
min_f = std::min(min_f, c[u][v] - mflow[u][v]);
}
for (v = dest; v != source; v = parent[v])
{
u = parent[v];
mflow[u][v] += min_f;
mflow[v][u] -= min_f;
}
max_flow += min_f;
}
}
ofstream out("maxflow.out", ios::out);
out << max_flow;
out.close();
return 0;
}