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#include <bits/stdc++.h>
#define int long long
using namespace std;
ifstream fin("maxflow.in");
ofstream fout("maxflow.out");
struct edge{
int a,b,flow,cap;
};
struct Dinic{
vector<edge> edges;
vector<vector<int>> g;
vector<int> level;
vector<int> next;
int s,t;
void build(int n , int _s , int _t){
g.resize(n+1) , level.resize(n+1),next.resize(n+1);
s = _s;
t = _t;
}
void add_edge(int a , int b , int cap){
int m = edges.size();
edges.push_back({a,b,0,cap});
edges.push_back({b,a,0,0});
g[a].push_back(m);
g[b].push_back(m+1);
};
bool bfs(){
queue<int> q;
q.push(s);
level[s]= 0;
while(!q.empty()){
int node = q.front();
q.pop();
for(auto i : g[node]){
edge x = edges[i];
if(x.cap-x.flow < 1 || level[x.b] != -1){
continue;
}
level[x.b] = level[node]+1;
q.push(x.b);
}
}
return level[t] != -1;
}
int dfs(int node , int pushed){
if(pushed==0){
return 0;
}
if(node == t) {
return pushed;
}
for(int& i = next[node]; i < (int)g[node].size(); ++i){
edge x = edges[g[node][i]];
if(x.cap-x.flow < 1 || level[x.b] != level[node]+1){
continue;
}
int flow = dfs(x.b, min(pushed, x.cap-x.flow));
if(flow==0){
continue;
}
edges[g[node][i]].cap -= flow;
edges[g[node][i]^1].cap += flow;
return flow;
}
return 0;
}
int flow(){
int ans = 0;
while(true){
fill(level.begin(),level.end(),-1);
if(!bfs()){
break;
}
fill(next.begin(),next.end(),0);
while(int add = dfs(s,INT_MAX)){
ans+=add;
}
}
return ans;
}
};
int32_t main()
{
cin.tie(nullptr)->sync_with_stdio(false);
int n,m;
fin>>n>>m;
Dinic G;
G.build(n,1,n);
for(int i=1 ;i<= m ; ++i){
int a ,b, cap;
fin>>a>>b>>cap;
G.add_edge(a,b,cap);
}
fout<<G.flow();
}