Implementera en edmonds_karp, fungerar inte ännu för viktade noder

p11506/p11506.cpp

@@ -3,7 +3,7 @@
 #include <list>
 #include <vector>
 #include <cmath>
-#include <limits>
+#include <queue>
 
 using namespace std;
 
@@ -22,9 +22,9 @@ struct Node
 
 struct Edge
 {
-    Edge(Node *n1, Node *n2, int capacity):n1{n1}, n2{n2}, capacity{capacity}, flow{0}
+    Edge(Node *n1, Node *n2, int cap):n1{n1}, n2{n2}, flow{0}
     {
-        capacity = min(min(n1->capacity, n2->capacity), capacity);
+        capacity = min(min(n1->capacity, n2->capacity), cap);
 
         n1->neighbours.push_back(this);
         n2->neighbours.push_back(this);
@@ -35,9 +35,77 @@ struct Edge
     int flow;
 };
 
-int edmonds_karp(vector<Node> m)
+Node *other_node(Edge *e, Node *curr)
 {
-    return 0;
+    if(e->n1 == curr)
+        return e->n2;
+
+    return e->n1;
+}
+
+int edmonds_karp(vector<Node> &m, Node *source, Node *sink)
+{
+    int max_flow = 0;
+    // Göra bra krejjer
+    Edge *es = new Edge(source, source, 200000);
+    while(true)
+    {
+        vector<Edge*> parent(m.size()+1, nullptr);
+
+        queue<Node*> q;
+        q.push(source);
+        parent[source->id] = es;
+
+        while(!q.empty())
+        {
+            Node *curr = q.front();
+            q.pop();
+
+            for(auto e : curr->neighbours)
+            {
+                Node *o = other_node(e, curr);
+                if(parent[o->id] == nullptr && e->capacity > e->flow)
+                {
+                    q.push(o);
+                    parent[o->id] = e;
+                }
+            }
+        }
+
+
+        // No (new) way to sink
+        if(parent[sink->id] == nullptr)
+            break;
+
+        int push_flow = 200000;
+
+        Edge *e = parent[sink->id];
+        Node *curr = sink;
+        while(curr != source)
+        {
+            push_flow = min(push_flow, (e->capacity - e->flow) );
+
+            curr = other_node(e, curr);
+            e = parent[curr->id];
+        }
+
+
+        e = parent[sink->id];
+        curr = sink;
+        while(curr != source)
+        {
+            e->flow += push_flow;
+
+            curr = other_node(e, curr);
+            e = parent[curr->id];
+        }
+
+        max_flow += push_flow;
+    }
+
+    delete es;
+
+    return max_flow;
 }
 
 int main()
@@ -53,9 +121,9 @@ int main()
 
         vector<Node> machines(num_machines);
         machines[0].id = 1;
-        machines[0].capacity = INT_MAX;
+        machines[0].capacity = 200000;
         machines[num_machines-1].id = num_machines;
-        machines[num_machines-1].capacity = INT_MAX;
+        machines[num_machines-1].capacity = 200000;
 
         for(int i = 0; i < num_machines-2; i++)
         {
@@ -79,16 +147,16 @@ int main()
         }
 
 
-        cout << edmonds_karp(machines) << endl;
+        cout << edmonds_karp(machines, &machines[0], &machines[num_machines-1]) << endl;
 
-//        for(auto m : machines)
-//        {
-//            cout << m.id << ":" << m.capacity << endl;
-//            for(auto n : m.neighbours)
-//            {
-//                cout << "\t" << n->n1->id << " <--> " << n->n2->id << ": " << n->capacity << endl;
-//            }
-//        }
+        for(auto m : machines)
+        {
+            cout << m.id << ":" << m.capacity << endl;
+            for(auto n : m.neighbours)
+            {
+                cout << "\t" << n->n1->id << " <--> " << n->n2->id << "  Cap: " << n->capacity << "   Flow: " << n->flow << endl;
+            }
+        }
 
     }