# HG changeset patch
# User athos
# Date 1119885933 0
# Node ID f8efed98d6a34420902a23c4b8e1fd22ab57428f
# Parent  b303c1741c9a6a7b29a9c257651b392872c7d58e
Only added comments.

diff -r b303c1741c9a -r f8efed98d6a3 demo/lp_maxflow_demo.cc
--- a/demo/lp_maxflow_demo.cc	Mon Jun 27 15:22:34 2005 +0000
+++ b/demo/lp_maxflow_demo.cc	Mon Jun 27 15:25:33 2005 +0000
@@ -34,26 +34,34 @@
   typedef typename G::OutEdgeIt OutEdgeIt;
   typedef typename G::InEdgeIt InEdgeIt;
   
+  //Define a map on the edges for the variables of the LP problem
   typename G::template EdgeMap<LpDefault::Col> x(g);
   lp.addColSet(x);
   
+  //Nonnegativity and capacity constraints
   for(EdgeIt e(g);e!=INVALID;++e) {
     lp.colUpperBound(x[e],cap[e]);
     lp.colLowerBound(x[e],0);
   }
 
+
+  //Flow conservation constraints for the nodes (except for 's' and 't')
   for(NodeIt n(g);n!=INVALID;++n) if(n!=s&&n!=t) {
     LpDefault::Expr ex;
     for(InEdgeIt  e(g,n);e!=INVALID;++e) ex+=x[e];
     for(OutEdgeIt e(g,n);e!=INVALID;++e) ex-=x[e];
     lp.addRow(ex==0);
   }
+  
+  //Objective function: the flow value entering 't'
   {
     LpDefault::Expr ex;
     for(InEdgeIt  e(g,t);e!=INVALID;++e) ex+=x[e];
     for(OutEdgeIt e(g,t);e!=INVALID;++e) ex-=x[e];
     lp.setObj(ex);
   }
+
+  //Maximization
   lp.max();
 
 #ifdef HAVE_GLPK
@@ -61,6 +69,7 @@
   lp.messageLevel(3);
 #endif
 
+  //Solve with the underlying solver
   lp.solve();
 
   return lp.primalValue();