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#include <bits/stdc++.h>
using namespace std;
using uint = unsigned int;
using ll = long long;
using ull = unsigned long long;
using pii = pair<int, int>;
using pll = pair<ll, ll>;
#define dbg(x) cerr<<#x": "<<(x)<<endl
#define dbg_p(x) cerr<<#x": "<<(x).first<<' '<<(x).second<<endl
#define dbg_v(x, n) {cerr<<#x"[]: ";for(long long _=0;_<n;++_)cerr<<(x)[_]<<' ';cerr<<endl;}
#define all(v) v.begin(), v.end()
#define fi first
#define se second
template<typename T1, typename T2>
ostream& operator <<(ostream &out, const pair<T1, T2> &item) {
out << '(' << item.first << ", " << item.second << ')';
return out;
}
template <typename T>
ostream& operator <<(ostream &out, const vector<T>& v) {
for(const auto &item : v) out << item << ' ';
return out;
}
const int N = 1010;
const int INF = 0x3f3f3f3f;
struct Edge {
int to, flow;
};
int source, sink;
int d[N], ptr[N];
vector<int> adj[N];
vector<Edge> edges;
void addEdge(int a, int b, int cap) {
adj[a].push_back(edges.size());
edges.push_back({b, cap});
adj[b].push_back(edges.size());
edges.push_back({a, 0});
}
bool bfs(int v) {
queue<int> q;
memset(d, INF, sizeof d);
for(q.push(v), d[v] = 0; !q.empty(); q.pop()) {
for(auto id : adj[v = q.front()]) {
int u = edges[id].to;
if(edges[id].flow && d[u] > d[v] + 1) {
d[u] = d[v] + 1;
q.push(u);
}
}
}
return d[sink] < INF;
}
int dfs(int v, int flow) {
if(v == sink || !flow) return flow;
for(; ptr[v] < adj[v].size(); ++ptr[v]) {
int id = adj[v][ptr[v]];
if(edges[id].flow && d[edges[id].to] == 1 + d[v]) {
int pushed = dfs(edges[id].to, min(flow, edges[id].flow));
if(pushed) {
edges[id].flow -= pushed;
edges[id ^ 1].flow += pushed;
return pushed;
}
}
}
return 0;
}
int dinic(int source) {
int flow, pushed;
for(flow = 0; bfs(source); ) {
memset(ptr, 0, sizeof ptr);
while(pushed = dfs(source, INF)) flow += pushed;
}
return flow;
}
int main()
{
ios_base::sync_with_stdio(false);
freopen("maxflow.in", "r", stdin);
freopen("maxflow.out", "w", stdout);
int n, m, a, b, c;
cin >> n >> m;
for(int i = 1; i <= m; ++i) {
cin >> a >> b >> c;
addEdge(a, b, c);
}
source = 1;
sink = n;
cout << dinic(source) << '\n';
return 0;
}