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#include <fstream>
#include <vector>
#include <queue>
using namespace std;
ifstream fin("maxflow.in");
ofstream fout("maxflow.out");
const int NMAX = 1001;
vector<vector<int>> edgIn, edgOut;
vector<int> tata;
int cap[NMAX][NMAX], flux[NMAX][NMAX];
int n, m;
bool BFS(int s, int t){
queue<int> q;
vector<int> viz(n+1, 0);
tata.resize(n+1, 0);
q.push(s);
while(!q.empty()){
int u = q.front();
q.pop();
for(auto &v:edgOut[u]){
if(!viz[v] && cap[u][v] - flux[u][v] > 0){
viz[v] = 1;
q.push(v);
tata[v] = u;
if(v == t)
return true;
}
}
for(auto &v:edgIn[u]){
if(!viz[v] && flux[v][u] > 0){
viz[v] = 1;
q.push(v);
tata[v] = -u;
if(v == t)
return true;
}
}
}
return false;
}
int capRezid(vector<int> &tata, int s, int t){
int mn = 200000;
for(int v = t; v!=s; v = abs(tata[v])){
if(tata[v] > 0){
mn = min(mn, cap[tata[v]][v] - flux[tata[v]][v]);
}
else{
mn = min(mn, flux[v][-tata[v]]);
}
}
return mn;
}
void actualizareFlux(vector<int> &tata, int s, int t, int cr){
for(int v = t; v!=s; v = abs(tata[v])){
if(tata[v] > 0){
flux[tata[v]][v] += cr;
}
else{
flux[v][-tata[v]] -= cr;
}
}
}
int main(){
fin>>n>>m;
edgIn.resize(n+1);
edgOut.resize(n+1);
while(m--){
int u, v, c;
fin>>u>>v>>c;
edgOut[u].push_back(v);
edgIn[v].push_back(u);
cap[u][v] = c;
}
int fluxmax = 0;
while(BFS(1, n)){
int cr = capRezid(tata, 1, n);
actualizareFlux(tata, 1, n, cr);
fluxmax += cr;
}
fout<<fluxmax;
return 0;
}