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#include <fstream>
#include <iostream>
#include <queue>
#include <algorithm>
#include <climits>
using namespace std;
ifstream in ("maxflow.in");
ofstream out ("maxflow.out");
int const nmax = 1000;
struct Edge {
int to; //g[from][i].to imi da muchia from->to
int rev; //g[to][rev] imi da muchia to->from
int cap;
int flow;
};
vector<Edge> g[1 + nmax];
int n, m, src, dest;
int cost[1 + nmax][1 + nmax];
void addedge(int i, int j) {
g[i].push_back({j, g[j].size(), cost[i][j], 0});
g[j].push_back({i, g[i].size() - 1, cost[j][i], 0});
}
int dist[1 + nmax];
bool bfs() {
fill(dist + 1, dist + n + 1, -1);
queue<int> q;
q.push(src);
dist[src] = 0;
while(0 < q.size()){
int from = q.front();
q.pop();
for(int i = 0 ; i < g[from].size() ;i++) {
Edge e = g[from][i];
if(dist[e.to] < 0 && e.flow < e.cap) {
dist[e.to] = dist[from] + 1;
q.push(e.to);
}
}
}
return (0 <= dist[dest]);
}
int dfs(int from, int deltaflow) { //dfs e facut pe level graph, nu pe graf
if(from == dest){
return deltaflow;
} else {
for(int i = 0 ; i < g[from].size() ;i++){
Edge &e = g[from][i];
if(dist[from] + 1 == dist[e.to]){
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 answer = 0;
while(bfs()) {
int deltaflow = dfs(src, INT_MAX);
while(0 < deltaflow) {
answer += deltaflow;
deltaflow = dfs(src, INT_MAX);
}
}
return answer;
}
int main() {
in >> n >> m;
src = 1;
dest = n;
for(int i = 0 ; i < m ;i++){
int x, y, z;
in >> x >> y >> z;
cost[x][y] = z;
}
for(int i = 1 ; i < n; i++){
for(int j = i + 1 ; j <= n; j++){
if(cost[i][j] != 0 || cost[j][i] != 0) {
addedge(i, j); //in problemele de flux sunt obligat sa inserez ambele muchii
}
}
}
out<<maxflow()<<endl;
return 0;
}