Pagini recente » Cod sursa (job #607433) | Cod sursa (job #2684630) | Cod sursa (job #762976) | Cod sursa (job #1300567) | Cod sursa (job #2065899)
#include <iostream>
#include <fstream>
#include <unordered_set>
#include <queue>
#include <stdio.h>
#include <stdlib.h>
#define MAX 999999
using namespace std;
int c[1000][1000];
int main()
{
ifstream in;
in.open("maxflow.in", ios::in);
int n, m, u, v, source, dest;
in >> n >> m;
source = 0;
dest = n - 1;
for (int i = 0; i < m; i++)
{
in >> u >> v;
in >> c[u - 1][v - 1];
}
in.close();
unordered_set<int> visited;
int parent[1000];
long max_flow = 0;
for (;;)
{
memset(parent, 0, sizeof(parent));
parent[source] = -1;
visited.clear();
visited.insert(source);
queue<int> q;
q.push(source);
visited.insert(source);
while (!q.empty())
{
int nod = q.front();
q.pop();
for (int i = 0; i < n; i++)
if (c[nod][i] > 0 && visited.find(i) == visited.end())
{
parent[i] = nod;
visited.insert(i);
q.push(i);
}
}
if (visited.find(dest) == visited.end())
break;
int min_f = MAX;
for (v = dest; v != source; v = parent[v])
{
u = parent[v];
if (c[u][v] < min_f)
min_f = c[u][v];
}
max_flow = max_flow + min_f;
for (v = dest; v != source; v = parent[v])
{
u = parent[v];
c[u][v] = c[u][v] - min_f;
c[v][u] = c[v][u] + min_f;
}
}
ofstream out("maxflow.out", ios::out);
out << max_flow;
out.close();
return 0;
}