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#include <bits/stdc++.h>
using namespace std;
ifstream in("maxflow.in");
ofstream out("maxflow.out");
const int NMAX = 1005;
struct Edge {
int to, cap, flow, rev;
};
vector<Edge> g[NMAX];
int dist[NMAX], src, dest, c[NMAX][NMAX], rem[NMAX], n, m;
void addEdge(int i, int j) {
Edge a = {j, c[i][j], 0, g[j].size()};
Edge b = {i, c[j][i], 0, g[i].size()};
g[i].push_back(a);
g[j].push_back(b);
}
bool bfs() {
for(int i = 1; i <= n; i ++)
dist[i] = -1;
queue<int> q;
dist[src] = 0;
q.push(src);
while(q.size()) {
int from = q.front();
q.pop();
for(auto it : g[from]) {
if(dist[it.to] == -1 && it.cap > it.flow) {
dist[it.to] = 1 + dist[from];
q.push(it.to);
}
}
}
return (0 <= dist[dest]);
}
int dfs(int from, int deltaflow) {
if(from == dest)
return deltaflow;
for(int i = rem[from]; i < g[from].size(); i ++) {
Edge &e = g[from][i];
if(dist[e.to] == dist[from] + 1) {
int addflow = dfs(e.to, min(deltaflow, e.cap - e.flow));
if(addflow > 0) {
Edge &rev = g[e.to][e.rev];
e.flow += addflow;
rev.flow -= addflow;
rem[from] = i;
return addflow;
}
}
}
return 0;
}
int dinic() {
int maxflow = 0;
while(bfs()) {
for(int i = 1; i <= n; i ++)
rem[i] = 0;
int aux = dfs(src, INT_MAX);
while(aux) {
maxflow += aux;
aux = dfs(src, INT_MAX);
}
}
return maxflow;
}
int main() {
ios::sync_with_stdio(false);
in.tie(NULL);
out.tie(NULL);
in >> n >> m;
src = 1;
dest = n;
for(int i = 1; i <= m; i ++) {
int x, y, z;
in >> x >> y >> z;
c[x][y] = z;
}
for(int i = 1; i <= n; i ++)
for(int j = i + 1; j <= n; j ++)
if(c[i][j] || c[j][i])
addEdge(i, j);
out << dinic();
return 0;
}