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#include <fstream>
#include <algorithm>
#include <cmath>
#include <vector>
#include <map>
#include <unordered_map>
#include <set>
#include <cstring>
#include <chrono>
#include <cassert>
#include <bitset>
#include <stack>
#include <queue>
#include <iomanip>
#include <random>
#include <string>
#include <complex>
//#include <ext/pb_ds/assoc_container.hpp>
#ifdef _MSC_VER
# include <intrin.h>
# define __builtin_popcount __popcnt
# define __builtin_popcountll __popcnt64
#endif
#pragma GCC optimize("Ofast")
//#pragma GCC target("sse,sse2,sse3,ssse3,sse4,popcnt,abm,mmx,avx,tune=native")
#define x first
#define y second
#define ld long double
#define ll long long
#define ull unsigned long long
#define us unsigned short
#define lsb(x) ((x) & (-(x)))
#define pii pair <int, int>
#define pll pair <ll, ll>
using namespace std;
//using namespace __gnu_pbds;
mt19937_64 gen(time(0));
uniform_int_distribution <int64_t> rng;
#ifdef LOCAL
ifstream cin("test.in");
ofstream cout("test.out");
#else
ifstream cin("maxflow.in");
ofstream cout("maxflow.out");
#endif
const int N = 20000;
struct Flow {
struct Edge {
int to;
int cap;
int ind;
};
int n;
int lvl[N + 5], idx[N + 5];
vector <Edge> g[N + 5];
void init(int _n) {
n = _n;
for (int i = 1; i <= n; i++)
g[i].clear();
}
void add_edge(int x, int y, int z) {
g[x].push_back({ y, z, (int)g[y].size() });
g[y].push_back({ x, 0, (int)g[x].size() - 1 });
}
bool bfs(int src, int dst) {
queue <int> q;
memset(lvl, 0, sizeof(lvl));
lvl[src] = 1;
q.push(src);
while (!q.empty()) {
int node = q.front();
q.pop();
int ind = 0;
for (auto &[son, cap, _] : g[node]) {
if (!lvl[son] && cap > 0) {
lvl[son] = lvl[node] + 1;
q.push(son);
}
}
}
return lvl[dst] > 0;
}
int dfs(int node, int dst, int flow = (int)1e9) {
if (node == dst)
return flow;
for (; idx[node] < g[node].size(); idx[node]++) {
auto& [son, cap, ind] = g[node][idx[node]];
if (cap <= 0 || lvl[son] != lvl[node] + 1)
continue;
int new_flow = dfs(son, dst, min(flow, cap));
if (new_flow) {
cap -= new_flow;
g[son][ind].cap += new_flow;
return new_flow;
}
lvl[son] = 0;
}
return 0;
}
int max_flow(int src, int dst) {
int total_flow = 0, flow;
while (bfs(src, dst)) {
memset(idx, 0, sizeof(idx));
while(flow = dfs(src, dst)) {
total_flow += flow;
}
}
return total_flow;
}
} flow;
int n, m;
void solve(int test) {
ld t1 = clock();
cin >> n >> m;
flow.init(n);
for (; m; m--) {
int x, y, z;
cin >> x >> y >> z;
flow.add_edge(x, y, z);
}
cout << flow.max_flow(1, n) << "\n";
#ifdef LOCAL
cout << (clock() - t1) / CLOCKS_PER_SEC << "s\n";
#endif
}
int main() {
ios_base::sync_with_stdio(false);
cin.tie(0); cout.tie(0);
srand(time(0));
int T = 1;
//cin >> T;
for (int t = 1; t <= T; t++) {
solve(t);
}
return 0;
}