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// Edmonds-Karp
// "Optimizarea" de 100p merge doar cand intra mai multe muchii in sink, altfel nu face nimic...
#include <bits/stdc++.h>
#define ll long long
using namespace std;
ifstream in("maxflow.in");
ofstream out("maxflow.out");
struct Edge {
int from;
int to;
int cap;
int flow;
};
struct EKMaxFlow {
int source;
int sink;
vector<Edge> edges;
vector<vector<pair<int, int> > > v;
vector<int> path;
vector<int> seen;
int N;
int M;
EKMaxFlow(int s, int d, int n, int m) : source(s), sink(d), v(n), path(n), seen(n), N(n), M(m) {}
void addEdge(int from, int to, int cap) {
edges.push_back({from, to, cap, 0});
v[from].push_back({to, (int) edges.size() - 1});
edges.push_back({to, from, 0, 0});
v[to].push_back({from, (int) edges.size() - 1});
}
bool canAugment() {
queue<int> q;
q.push(source);
fill(seen.begin(), seen.end(), 0);
seen[source] = 1;
while (!q.empty()) {
int node = q.front();
q.pop();
if (node == sink) {
return true;
}
for (auto nxt : v[node]) {
if (!seen[nxt.first]) {
int resCap = edges[nxt.second].cap - edges[nxt.second].flow;
if (resCap > 0) {
seen[nxt.first] = 1;
q.push(nxt.first);
path[nxt.first] = nxt.second;
}
}
}
}
return false;
}
int maxFlow() {
int flow = 0;
while (canAugment()) {
for (auto pv : v[sink]) {
int mn = INT_MAX;
int validPath = 1;
for (int edgeId = pv.second ^ 1; ; edgeId = path[edges[edgeId].from]) {
int resCap = edges[edgeId].cap - edges[edgeId].flow;
mn = min(mn, resCap);
validPath &= seen[edges[edgeId].from];
if (edges[edgeId].from == source) {
break;
}
}
if (!validPath) {
continue;
}
flow += mn;
for (int edgeId = pv.second ^ 1; ; edgeId = path[edges[edgeId].from]) {
edges[edgeId].flow += mn;
edges[edgeId ^ 1].flow -= mn;
if (edges[edgeId].from == source) {
break;
}
}
}
}
return flow;
}
};
int main() {
int n, m;
in >> n >> m;
EKMaxFlow graph(0, n - 1, n, m);
for (int i = 0, x, y, c; i < m; i++) {
in >> x >> y >> c;
x--;
y--;
graph.addEdge(x, y, c);
}
out << graph.maxFlow();
return 0;
}