Changeset 1117:b40c2bbb8da5 in lemon-main

Timestamp:

08/19/13 22:35:54 (11 years ago)

Author:

Peter Kovacs <kpeter@…>

Branch:

default

Phase:

public

Message:

Fix division by zero error in case of empty graph (#474)

Files:

• lemon/network_simplex.h (modified) (1 diff)
• test/min_cost_flow_test.cc (modified) (1 diff)

lemon/network_simplex.h

@@ -930 +930 @@
         _node_id[n] = i;
       }
-      if (_arc_mixing) {
+      if (_arc_mixing && _node_num > 1) {
         // Store the arcs in a mixed order
         const int skip = std::max(_arc_num / _node_num, 3);

test/min_cost_flow_test.cc

@@ -396 +396 @@
   checkMcf(mcf3, mcf3.run(param), neg2_gr, neg2_l, neg2_u, neg2_c, neg2_s,
            mcf3.OPTIMAL, true,     -300, test_str + "-18", GEQ);
+
+  // Tests for empty graph
+  Digraph gr0;
+  MCF mcf0(gr0);
+  mcf0.run(param);
+  check(mcf0.totalCost() == 0, "Wrong total cost");  
 }