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// By Stefan Radu
#include <algorithm>
#include <fstream>
#include <iomanip>
#include <cassert>
#include <vector>
#include <string>
#include <cctype>
#include <queue>
#include <deque>
#include <cmath>
#include <stack>
#include <map>
#include <set>
using namespace std;
ifstream cin("maxflow.in");
ofstream cout("maxflow.out");
#define sz(x) (int)(x).size()
typedef pair < int, int > pii;
typedef long long ll;
typedef long double ld;
typedef unsigned int ui;
typedef unsigned long long ull;
vector < vector < int > > gr(1001);
vector < int > lvl(1001), used(1001);
vector < vector < int > > currentFlow(1001, vector < int > (1001));
vector < vector < int > > maxCap(1001, vector < int > (1001));
int cnt = 0, s, t;
bool bfs() {
++ cnt;
queue < int > q;
q.push(s);
lvl[s] = 1;
while (not q.empty()) {
auto curNode = q.front();
q.pop();
if (curNode == t) return true;
for (auto x : gr[curNode]) {
if (lvl[x]) continue;
if (currentFlow[curNode][x] < maxCap[curNode][x]) {
lvl[x] = lvl[curNode] + 1;
q.push(x);
}
}
}
return false;
}
ll dfs(int curNode, ll flow) {
used[curNode] = cnt;
if (curNode == t) return flow;
int ret = 0;
for (auto x : gr[curNode]) {
if (used[x] == cnt) continue;
if (lvl[x] == lvl[curNode] + 1 and currentFlow[curNode][x] < maxCap[curNode][x]) {
auto k = dfs(x, min(flow, 1ll * maxCap[curNode][x] - currentFlow[curNode][x]));
currentFlow[curNode][x] += k;
currentFlow[x][curNode] -= k;
flow -= k;
ret += k;
if (flow == 0) break;
}
}
return ret;
}
int main() {
#ifdef STEF
freopen("input", "r", stdin);
freopen("output", "w", stdout);
#endif
ios::sync_with_stdio(false);
cin.tie(0);cout.tie(0);
int n, m;
cin >> n >> m;
for (int i = 1; i <= m; ++ i) {
int a, b, c;
cin >> a >> b >> c;
gr[a].push_back(b);
maxCap[a][b] = c;
}
s = 1, t = n;
ll maxFlow = 0;
while (bfs()) {
maxFlow += dfs(s, 2e18);
fill(lvl.begin(), lvl.end(), 0);
}
cout << maxFlow << '\n';
}