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#include <fstream>
#include <vector>
#include <cstring>
#include <string>
#include <queue>
#include <climits>
#define NMAX 1024
#define pb push_back
#define INF INT_MAX
using namespace std;
ifstream f("maxflow.in");
ofstream g("maxflow.out");
int n, m;
vector<int> G[NMAX];
int flow_cap[NMAX][NMAX];
bool visited[NMAX];
int parent[NMAX];
void read_data(){
f >> n >> m;
for(int i = 1; i<=m; i++){
int x, y, c;
f >> x >> y >> c;
G[x].pb(y);
G[y].pb(x);
flow_cap[x][y] += c;
}
}
bool bfs(int source, int dest){
memset(visited, false, sizeof(visited));
memset(parent, 0, sizeof(parent));
visited[source] = true;
parent[source] = -1;
queue<int> q;
q.push(source);
while(!q.empty()){
int node = q.front();
q.pop();
if(node == dest){
continue;
}
for(const auto& adj : G[node]){
if(!visited[adj] && flow_cap[node][adj] > 0){
q.push(adj);
visited[adj] = true;
parent[adj] = node;
}
}
}
return visited[dest];
}
int get_flow(int source, int dest){
int max_flow = 0, min_cap;
while(bfs(source, dest)){
for(const auto& curr_node : G[dest]){
if(!visited[curr_node] || flow_cap[curr_node][dest] <= 0){
continue;
}
min_cap = INF;
parent[dest] = curr_node;
for(int i = dest; i != source; i = parent[i]){
min_cap = min(min_cap, flow_cap[parent[i]][i]);
}
for(int i = dest; i != source; i = parent[i]){
flow_cap[parent[i]][i] -= min_cap;
flow_cap[i][parent[i]] += min_cap;
}
max_flow += min_cap;
}
}
return max_flow;
}
int main(){
read_data();
g << get_flow(1, n);
return 0;
}