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#include <bits/stdc++.h>
using namespace std;
/*
int n, m, c[N][N], p[N];
bool viz[N];
queue <int> Q;
vector <int> v[N];
bool bfs(int s, int t){
for (int i=1; i<=n; i++) viz[i] = 0;
viz[s] = 1; Q.push(s);
while (!Q.empty()){
int nod = Q.front();
Q.pop();
if (nod == n) continue;
for (auto it: v[nod]){
if (viz[it] || !c[nod][it]) continue;
viz[it] = 1; Q.push(it); p[it] = nod;
}
}
return viz[t];
}
int EdmondsKarp(int s, int t){
int maxflow = 0;
while (bfs(s, t)){
for (auto it: v[n]){
if (!viz[it] || !c[it][n]) continue;
int flow = 1e9;
p[n] = it;
for (int nod = t; nod != s; nod = p[nod])
flow = min(flow, c[p[nod]][nod]);
for (int nod = t; nod != s; nod = p[nod]){
c[p[nod]][nod] -= flow;
c[nod][p[nod]] += flow;
}
maxflow += flow;
}
}
return maxflow;
}
*/
#define N 1005
int n, m, c[N][N], fv[2*N];
struct node{
int eflow, h;
} ver[N];
bool inq[N];
queue <int> Q;
void preFlow(int s){
for (int i=1; i<=n; i++) ver[i] = {0, 0};
ver[s].h = n; fv[n]++;
for (int i=1; i<=n; i++){
if (i != s && c[s][i]) Q.push(i), ver[i].eflow += c[s][i], c[i][s] += c[s][i], c[s][i] = 0, inq[i] = 1;
}
}
void push(int q){
for (int i=1; i<=n && ver[q].eflow; i++){
if (i == q || !c[q][i]) continue;
if (ver[q].h > ver[i].h){
int flow = min(c[q][i], ver[q].eflow);
ver[q].eflow -= flow;
ver[i].eflow += flow;
c[q][i] -= flow;
c[i][q] += flow;
if (!inq[i]) Q.push(i), inq[i] = 1;
}
}
return;
}
void normalize_h(int qh){
if (!fv[qh]){
for (int i=1; i<=n; i++)
if (ver[i].h > qh) fv[ver[i].h]--, ver[i].h = qh, fv[qh]++;
}
}
void relabel(int q){
ver[q].h++;
fv[ver[q].h - 1]--;
fv[ver[q].h]++;
normalize_h(ver[q].h - 1);
}
int push_relabel(int s, int t){
preFlow(s);
//inq[s] = inq[t] = 1;
while (!Q.empty()){
int u = Q.front();
Q.pop();
if (u == t || u == s) continue;
inq[u] = 0;
while (ver[u].eflow){
push(u);
if (ver[u].eflow) relabel(u);
}
}
return ver[t].eflow;
}
int main(){
ifstream cin ("maxflow.in");
ofstream cout ("maxflow.out");
cin >> n >> m;
for (int i=1, x, y, z; i<=m; i++){
cin >> x >> y >> z;
c[x][y] += z;
}
cout << push_relabel(1, n) << '\n';
//for (int i=1; i<=n; i++)
// if (ver[i].eflow) cout << i << ": " << ver[i].eflow << '\n';
return 0;
}