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// Dinic O(V^2 * E)
#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;
ll cap;
ll flow;
Edge(int x, int y, ll c) : from(x), to(y), cap(c), flow(0) {}
ll resCap() {
return cap - flow; // residual capacity
}
};
struct DinicMaxFlow {
const ll inf = 1e18;
bool isDirected;
int source;
int sink;
vector<Edge> edges;
vector<vector<int> > v;
vector<int> level;
vector<int> lst;
int N;
int M;
DinicMaxFlow(bool dir, int s, int d, int n) : isDirected(dir), source(s), sink(d), v(n), level(n), lst(n), N(n), M(0) {}
void addEdge(int from, int to, int cap) {
/*
Pentru un graf neorientat si o muchie x y cap putem apela:
addEdge(x, y, cap)
*/
edges.push_back(Edge(from, to, cap));
edges.push_back(Edge(to, from, (isDirected ? 0 : cap)));
v[from].push_back(M++);
v[to].push_back(M++);
}
// the layered network has no cycles obv
bool canPush() {
queue<int> q;
fill(level.begin(), level.end(), -1);
level[source] = 0;
q.push(source);
while (!q.empty()) {
int node = q.front();
q.pop();
if (node == sink) {
return true;
}
for (auto edgeId : v[node]) {
int nxt = edges[edgeId].to;
if (level[nxt] == -1) {
if (edges[edgeId].resCap() > 0) {
level[nxt] = level[node] + 1;
q.push(nxt);
}
}
}
}
return false;
}
ll push(int node, ll pushedFlow) {
if (pushedFlow == 0) {
return 0;
}
if (node == sink) {
return pushedFlow;
}
for (; lst[node] < (int) v[node].size(); lst[node]++) { // nu trecem printr-o muchie de mai multe ori
int edgeId = v[node][lst[node]];
int nxt = edges[edgeId].to;
auto resCap = edges[edgeId].resCap();
if (level[node] + 1 != level[nxt] || resCap <= 0) {
continue;
}
auto flow = push(nxt, min(pushedFlow, resCap));
if (flow == 0) {
continue;
}
edges[edgeId].flow += flow;
edges[edgeId ^ 1].flow -= flow;
return flow;
}
return 0;
}
ll maxFlow() {
ll flow = 0;
while (canPush()) {
fill(lst.begin(), lst.end(), 0);
while (auto pushedFlow = push(source, inf)) {
flow += pushedFlow;
}
}
return flow;
}
};
int main() {
int n, m;
in >> n >> m;
DinicMaxFlow graph(true, 0, n - 1, n);
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;
}