1.1 --- a/lemon/network_simplex.h	Sat Mar 20 11:03:12 2010 +0100
     1.2 +++ b/lemon/network_simplex.h	Sat Mar 16 16:20:41 2013 +0100
     1.3 @@ -1067,6 +1067,10 @@
     1.4        if ( !((_stype == GEQ && _sum_supply <= 0) ||
     1.5               (_stype == LEQ && _sum_supply >= 0)) ) return false;
     1.6  
     1.7 +      // Check lower and upper bounds
     1.8 +      LEMON_DEBUG(checkBoundMaps(),
     1.9 +          "Upper bounds must be greater or equal to the lower bounds");
    1.10 +
    1.11        // Remove non-zero lower bounds
    1.12        if (_have_lower) {
    1.13          for (int i = 0; i != _arc_num; ++i) {
    1.14 @@ -1230,6 +1234,15 @@
    1.15  
    1.16        return true;
    1.17      }
    1.18 +    
    1.19 +    // Check if the upper bound is greater or equal to the lower bound
    1.20 +    // on each arc.
    1.21 +    bool checkBoundMaps() {
    1.22 +      for (int j = 0; j != _arc_num; ++j) {
    1.23 +        if (_upper[j] < _lower[j]) return false;
    1.24 +      }
    1.25 +      return true;
    1.26 +    }
    1.27  
    1.28      // Find the join node
    1.29      void findJoinNode() {