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#include <climits>
#include <vector>
#include <fstream>
#include <queue>
using namespace std;
ifstream in("maxflow.in");
ofstream out("maxflow.out");
int BFS(int s, int n, vector<vector<int>> &adjList, vector<vector<int>> &adjListIn,
vector<vector<long>> &flux, vector<vector<long>> &cost, vector<int> &tata) {
queue<int> queue;
vector<int> viz(n+1, 0);
for (int i = 0; i <= n; i++)
tata[i] = 0;
queue.push(s);
viz[s] = 1;
while (!queue.empty()) {
int x;
x = queue.front();
queue.pop();
for (int i = 0; i < adjList[x].size(); i++) {
int y;
y = adjList[x][i];
if (viz[y] == 0 && flux[x][y] < cost[x][y]) {
queue.push(y);
viz[y] = 1;
tata[y] = x;
if (y == n) return 1;
}
}
for (int i = 0; i < adjListIn[x].size(); i++) {
int y;
y = adjListIn[x][i];
if (viz[y] == 0 && flux[y][x] > 0) {
queue.push(y);
viz[y] = 1;
tata[y] = -x;
if (y == n) return 1;
}
}
}
return 0;
}
int main() {
int n, m;
// citire date intrare
in >> n >> m;
vector<vector<int>> adjList(n+1);
vector<vector<int>> adjListIn(n+1);
vector<vector<long>> flux(n+1, vector<long> (n+1, 0)); //!!!
vector<vector<long>> cost(n+1, vector<long> (n+1, 0));
for (int i = 1; i <= m; i++) {
int x, y, c;
in >> x >> y >> c;
adjList[x].push_back(y);
adjListIn[y].push_back(x); // liste adiacenta intrare
cost[x][y] = c;
}
long fluxMax = 0;
int s = 1; // sursa
int t = n; // destinatia
vector<int> tata(n+1);
while (BFS(s, n, adjList, adjListIn, flux, cost, tata)) {
// calculam i(P) = capacitatea reziduala minima pe un arc de pe drumul
// de adjList s adjList t determinat cu bf
long iP = LONG_MAX; // i(P)
t = n;
while (t != s) {
if (tata[t] >= 0) { // arc direct - capacitate c(e)-flux(e)
if (cost[tata[t]][t] - flux[tata[t]][t] < iP)
iP = cost[tata[t]][t] - flux[tata[t]][t];
t = tata[t];
} else { // arc invers - capacitate flux(e)
if (flux[t][-tata[t]] < iP) iP = flux[t][-tata[t]];
t = -tata[t];
}
}
// revizuim fluxul de-a lungul lantului determinat
t = n;
while (t != s) {
if (tata[t] >= 0) { // arc direct - creste fluxul cu iP
flux[tata[t]][t] += iP;
t = tata[t];
} else { // arc invers - scade fluxul cu iP
flux[t][-tata[t]] -= iP;
t = -tata[t];
}
}
fluxMax += iP; // creste valoarea fluxului cu iP
}
out << fluxMax;
out.close();
in.close();
return 0;
}