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#include <iostream>
#include <fstream>
#include <vector>
#include <algorithm>
#include <cassert>
#include <cmath>
#include <queue>
using namespace std;
ifstream in ("maxflow.in");
ofstream out ("maxflow.out");
#define MIN(a, b) (((a) < (b)) ? (a) : (b))
#define MAX(a, b) (((a) < (b)) ? (b) : (a))
using ll = long long;
int const nmax = 100000;
int const inf = 1000000000;
class Graph{
private:
struct Edge{
int to;
int flow;
int cap;
int rev;
};
vector<vector<Edge>> g;
vector<int> level, rem;
int n;
int source, sink;
public:
Graph(int n_){
n = n_;
g.resize(1 + n);
level.resize(1 + n);
rem.resize(1 + n);
source = 1;
sink = n;
}
void addedge(int x, int y, int cap){
g[x].push_back({y, 0, cap, g[y].size()});
g[y].push_back({x, 0, 0, g[x].size() - 1});
}
bool BFS(){
for(int i = 1; i <= n; i++)
level[i] = 0;
level[source] = 1;
queue<int> q;
q.push(source);
while(0 < q.size()) {
int node = q.front();
q.pop();
for(int h = 0; h < g[node].size(); h++){
Edge e = g[node][h];
if(e.flow < e.cap && level[e.to] == 0){
level[e.to] = level[node] + 1;
q.push(e.to);
}
}
}
return 0 < level[sink];
}
int DFS(int node, int deltaflow){
if(node == sink){
return deltaflow;
} else {
for(int &h = rem[node]; h < g[node].size(); h++){
Edge &e = g[node][h];
if(level[node] + 1 == level[e.to] && e.flow < e.cap){
int delta = DFS(e.to, MIN(deltaflow, e.cap - e.flow));
if(0 < delta){
e.flow += delta;
g[e.to][e.rev].flow -= delta;
return delta;
}
}
}
return 0;
}
}
int maxflow(){
int result = 0;
while(BFS()){
for(int i = 1;i <= n; i++)
rem[i] = 0;
int delta = 0;
do {
result += delta;
delta = DFS(source, inf);
} while(0 < delta);
}
return result;
}
};
int main()
{
int n, m;
cin >> n >> m;
Graph graph(n);
for(int i = 1;i <= m; i++){
int x, y, cost;
cin >> x >> y >> cost;
graph.addedge(x, y, cost);
}
cout << graph.maxflow();
return 0;
}