Cod sursa(job #2953764)

Utilizator smunteanuMunteanu Stefan Catalin smunteanu Data 12 decembrie 2022 02:50:38
Problema Flux maxim Scor 10
Compilator cpp-64 Status done
Runda Arhiva educationala Marime 1.3 kb
#include <bits/stdc++.h>
using namespace std;

const int nmax = 1007;

int n, m;
vector<int> adj[nmax];
int cap[nmax][nmax];
int par[nmax];

void dfs(int u) {
  for (int v : adj[u]) {
    if (par[v] == 0 && cap[u][v]) {
      par[v] = u;
      dfs(v);
    }
  }
}

int solve() {

  cin >> n >> m;

  for (int i = 0; i < m; i++) {
    int u, v, c;
    cin >> u >> v >> c;
    adj[u].push_back(v);
    adj[v].push_back(u);
    cap[u][v] = c;
  }

  int flow = 0;

  for (;;) {

    memset(par, 0, sizeof(par));

    dfs(1);

    if (!par[n]) return flow;

    for (int v : adj[n]) {
      
      if (par[v] == 0 || cap[v] == 0) continue;

      par[n] = v;

      int currentFlow = INT_MAX;

      for (int u = n; u != 1; u = par[u]) {
        currentFlow = min(currentFlow, cap[par[u]][u]);
      }

      if (currentFlow == 0) continue;

      for (int u = n; u != 1; u = par[u]) {
        cap[par[u]][u] -= currentFlow;
        cap[u][par[u]] += currentFlow;
      }

      flow += currentFlow;

    }

  }

}

int main() {
  
  #ifdef LOCAL
  freopen("file.in", "r", stdin);
  #else
  freopen("maxflow.in", "r", stdin);
  freopen("maxflow.out", "w", stdout);
  #endif

  ios_base::sync_with_stdio(false), cin.tie(NULL);

  cout << solve() << endl;

}