Changeset 901:30d5f950aa5f in lemon-1.2

Timestamp:

02/25/11 21:37:47 (13 years ago)

Author:

Alpar Juttner <alpar@…>

Branch:

default

Children:

902:79fab87ee483, 903:8ae2627aba1a

Phase:

public

Message:

Fix wrong initialization in Preflow (#414)

Files:

• lemon/preflow.h (modified) (2 diffs)
• test/preflow_test.cc (modified) (2 diffs)

lemon/preflow.h

@@ -526 +526 @@
           _flow->set(e, (*_capacity)[e]);
           (*_excess)[u] += rem;
-          if (u != _target && !_level->active(u)) {
-            _level->activate(u);
-          }
         }
       }
@@ -538 +535 @@
           _flow->set(e, 0);
           (*_excess)[v] += rem;
-          if (v != _target && !_level->active(v)) {
-            _level->activate(v);
-          }
-        }
-      }
+        }
+      }
+      for (NodeIt n(_graph); n != INVALID; ++n) 
+        if(n!=_source && n!=_target && _tolerance.positive((*_excess)[n]))
+          _level->activate(n);
+          
       return true;
     }

test/preflow_test.cc

@@ -152 +152 @@
 }
 
+void initFlowTest()
+{
+  DIGRAPH_TYPEDEFS(SmartDigraph);
+  
+  SmartDigraph g;
+  SmartDigraph::ArcMap<int> cap(g),iflow(g);
+  Node s=g.addNode(); Node t=g.addNode();
+  Node n1=g.addNode(); Node n2=g.addNode();
+  Arc a;
+  a=g.addArc(s,n1); cap[a]=20; iflow[a]=20;
+  a=g.addArc(n1,n2); cap[a]=10; iflow[a]=0;
+  a=g.addArc(n2,t); cap[a]=20; iflow[a]=0;
+
+  Preflow<SmartDigraph> pre(g,cap,s,t);
+  pre.init(iflow);
+  pre.startFirstPhase();
+  check(pre.flowValue() == 10, "The incorrect max flow value.");
+  check(pre.minCut(s), "Wrong min cut (Node s).");
+  check(pre.minCut(n1), "Wrong min cut (Node n1).");
+  check(!pre.minCut(n2), "Wrong min cut (Node n2).");
+  check(!pre.minCut(t), "Wrong min cut (Node t).");
+}
+
+
 int main() {
 
@@ -242 +266 @@
         "The max flow value or the three min cut values are incorrect.");
 
+  initFlowTest();
+  
   return 0;
 }