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#include <bits/stdc++.h>
using namespace std;
class Graph{
public:
const int N;
vector<vector<int>> neighbors;
vector<vector<int>> capacity;
public:
Graph(const int& N): N(N){
neighbors.resize(N);
capacity.assign(N, vector<int>(N));
}
void addEdge(int x, int y, int c){
neighbors[x].push_back(y);
neighbors[y].push_back(x);
capacity[x][y] = c;
}
};
class EdmondsKarp{
private:
const Graph& G;
const int N;
const int SRC;
const int DEST;
const int INF = 1e8;
vector<vector<int>> f;
vector<bool> vis;
vector<int> prev;
int augmentingPath(){
fill(vis.begin(), vis.end(), false);
fill(prev.begin(), prev.end(), INF);
queue<int> q;
q.push(SRC);
vis[SRC] = true;
while(!q.empty() && !vis[DEST]){
int node = q.front();
q.pop();
for(int nextNode: G.neighbors[node]){
int remainingCapacity = G.capacity[node][nextNode] - f[node][nextNode];
if(!vis[nextNode] && remainingCapacity > 0){
vis[nextNode] = true;
prev[nextNode] = node;
q.push(nextNode);
}
}
}
int delta = 0;
if(vis[DEST]){
delta = INF;
for(int node = DEST; node != SRC; node = prev[node]){
int remainingCapacity = G.capacity[prev[node]][node] - f[prev[node]][node];
delta = min(delta, remainingCapacity);
}
for(int node = DEST; node != SRC; node = prev[node]){
f[prev[node]][node] += delta;
f[node][prev[node]] -= delta;
}
}
return delta;
}
public:
EdmondsKarp(const Graph& G, const int& SRC, const int& DEST):
G(G), N(G.N), SRC(SRC), DEST(DEST){
}
int computeMaxFlow(){
f.assign(N, vector<int>(N, 0));
vis.resize(N);
prev.resize(N);
int maxFlow = 0;
bool containsAugmentingPath = true;
while(containsAugmentingPath){
int delta = augmentingPath();
if(delta > 0){
maxFlow += delta;
}else{
containsAugmentingPath = false;
}
}
return maxFlow;
}
};
int main(){
ifstream cin("maxflow.in");
ofstream cout("maxflow.out");
int N, M;
cin >> N >> M;
Graph G(N);
int x, y, c;
for(int i = 0; i < M; ++i){
cin >> x >> y >> c;
G.addEdge(x - 1, y - 1, c);
}
cout << EdmondsKarp(G, 0, N - 1).computeMaxFlow();
cin.close();
cout.close();
return 0;
}