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#include <bits/stdc++.h>
//Soltan Cristian
#define fri(a, b) for (int i = (a); i < (b); ++i)
#define frj(a, b) for(int j = a; j < b; j++)
#define frk(a, b) for(int k = a; k < b; k++)
#define frm(a, b, i) for(int i = b; i >= a; i--)
#define ll long long
#define all(x) x.begin(), x.end()
#define mod 1000000007
#define pb push_back
#define st first
#define nd second
#define sz(x) (ll)x.size()
#define rall(x) x.rbegin(), x.rend()
#define ct(x) cout << x
#define cts(x) cout << x << ' '
#define ctn(x) cout << x << '\n'
#define Y cout << "YES" << '\n'
#define N cout << "NO" << '\n'
using namespace std;
using vi = vector<int>;
using vl = vector<ll>;
using vs = vector<string>;
using vb = vector<bool>;
using ml = map<ll, ll>;
using vii = vector<vector<int>>;
using vll = vector<vector<ll>>;
using pii = pair<int, int>;
using pll = pair<ll, ll>;
const int dx[] = {-1, 0, 1, 0};
const int dy[] = {0, 1, 0, -1};
template <typename T>void read(T n, vector<T> &a){fri(0, n){cin >> a[i];}}
template<typename T>void print(T n, T m, vector<vector<T>> &dp){fri(0, n){ct('\n');frj(0, m){ct(setw(5));cts(dp[i][j]);}}}
const int mxa = 2 * 1e5 + 2;
// string __fname = "submultimi";
// ifstream in(__fname + ".in");
// ofstream out (__fname + ".out");
// #define cin in
// #define cout out
int n, m;
struct FlowEdge {
int u, v;
long long cap, flow = 0;
};
vector<vector<int>> adj;
vector<FlowEdge> edges;
vector<int> level;
vector<int> ptr;
bool bfs(){
queue<int> q;
q.push(1);
level[1] = 0;
while(!q.empty()){
int u = q.front();
q.pop();
for(auto id : adj[u]){
if(level[edges[id].v] == -1 && edges[id].cap - edges[id].flow > 0){
level[edges[id].v] = level[u] + 1;
q.push(edges[id].v);
}
}
}
return level[n] != -1;
}
ll dfs(int u, ll mxf){
if(mxf == 0){
return 0;
}
if(u == n){
return mxf;
}
for(int& v = ptr[u]; v < sz(adj[u]); v++){
int id = adj[u][v];
if(level[edges[id].v] != level[u] + 1 || edges[id].cap - edges[id].flow < 1) continue;
ll fl = dfs(edges[id].v, min(mxf, edges[id].cap - edges[id].flow));
if(fl == 0){
continue;
}
edges[id].flow += fl;
edges[id ^ 1].flow -= fl;
return fl;
}
return 0;
}
void solve(){
cin >> n >> m;
adj.resize(n + 1);
edges.resize(m * 2 + 1);
int k = 0;
for(int i = 0 ; i < m; i++){
int a, b, c;
cin >> a >> b >> c;
adj[a].push_back(k);
adj[b].push_back(k + 1);
edges[k].u = a; edges[k].v = b;
edges[k].cap = c;
edges[k + 1].u = b; edges[k + 1].v = a;
edges[k + 1].cap = 0;
k += 2;
}
int rs = 0;
level.resize(n + 1);
ptr.resize(n + 1);
while (true) {
fill(level.begin(), level.end(), -1);
if (!bfs())
break;
fill(ptr.begin(), ptr.end(), 0);
while (long long pushed = dfs(1, 1e9)) {
rs += pushed;
}
}
cout << rs << '\n';
}
int main()
{
// ios_base::sync_with_stdio(0); cin.tie(0); ct(fixed); ct(setprecision(10));
// int t;
// cin >> t;
// while(t--)
solve();
return 0;
}