diff -r eb37b9774ef6 -r 2aabce558574 lemon/lp_base.h
--- a/lemon/lp_base.h	Thu Feb 15 13:06:23 2007 +0000
+++ b/lemon/lp_base.h	Thu Feb 15 14:22:08 2007 +0000
@@ -27,93 +27,16 @@
 #include<limits>
 #include<cmath>
 
-#include<lemon/bits/utility.h>
 #include<lemon/error.h>
 #include<lemon/bits/invalid.h>
+#include<lemon/bits/utility.h>
+#include<lemon/bits/lp_id.h>
 
 ///\file
 ///\brief The interface of the LP solver interface.
 ///\ingroup gen_opt_group
 namespace lemon {
 
-
-  ///Internal data structure to convert floating id's to fix one's
-    
-  ///\todo This might be implemented to be also usable in other places.
-  class _FixId 
-  {
-  protected:
-    int _first_index;
-    int first_free;
-  public:
-    std::vector<int> index;
-    std::vector<int> cross;
-    _FixId() : _first_index(-1), first_free(-1) {};
-    ///Convert a floating id to a fix one
-
-    ///\param n is a floating id
-    ///\return the corresponding fix id
-    int fixId(int n) const {return cross[n];}
-    ///Convert a fix id to a floating one
-
-    ///\param n is a fix id
-    ///\return the corresponding floating id
-    int floatingId(int n) const { return index[n];}
-    ///Add a new floating id.
-
-    ///\param n is a floating id
-    ///\return the fix id of the new value
-    ///\todo Multiple additions should also be handled.
-    int insert(int n)
-    {
-      if(cross.empty()) _first_index=n;
-      if(n>=int(cross.size())) {
-	cross.resize(n+1);
-	if(first_free==-1) {
-	  cross[n]=index.size();
-	  index.push_back(n);
-	}
-	else {
-	  cross[n]=first_free;
-	  int next=index[first_free];
-	  index[first_free]=n;
-	  first_free=next;
-	}
-	return cross[n];
-      }
-      else {
-	///\todo Create an own exception type.
-	throw LogicError(); //floatingId-s must form a continuous range;
-      }
-    }
-    ///Remove a fix id.
-
-    ///\param n is a fix id
-    ///
-    void erase(int n) 
-    {
-      int fl=index[n];
-      index[n]=first_free;
-      first_free=n;
-      for(int i=fl+1;i<int(cross.size());++i) {
-	cross[i-1]=cross[i];
-	index[cross[i]]--;
-      }
-      cross.pop_back();
-    }
-    ///An upper bound on the largest fix id.
-
-    ///\todo Do we need this?
-    ///
-    std::size_t maxFixId() { return cross.size()-1; }
-  
-    ///Returns the first (smallest) inserted index
-
-    ///Returns the first (smallest) inserted index
-    ///or -1 if no index has been inserted before.
-    int firstIndex() {return _first_index;}
-  };
-
   ///Common base class for LP solvers
   
   ///\todo Much more docs
@@ -121,9 +44,10 @@
   class LpSolverBase {
 
   protected:
-    _FixId rows;
-    _FixId cols;
 
+    _lp_bits::LpId rows;
+    _lp_bits::LpId cols;
+    
   public:
 
     ///Possible outcomes of an LP solving procedure
@@ -215,14 +139,12 @@
       ColIt() {}
       ColIt(LpSolverBase &lp) : _lp(&lp)
       {
-	id = _lp->cols.cross.empty()?-1:
-	  _lp->cols.fixId(_lp->cols.firstIndex());
+        _lp->cols.firstFix(id);
       }
       ColIt(const Invalid&) : Col(INVALID) {}
       ColIt &operator++() 
       {
-	int fid = _lp->cols.floatingId(id)+1;
-	id = unsigned(fid)<_lp->cols.cross.size() ? _lp->cols.fixId(fid) : -1;
+        _lp->cols.nextFix(id);
 	return *this;
       }
     };
@@ -746,8 +668,6 @@
     virtual Value _getColLowerBound(int i) = 0;
     virtual void _setColUpperBound(int i, Value value) = 0;
     virtual Value _getColUpperBound(int i) = 0;
-//     virtual void _setRowLowerBound(int i, Value value) = 0;
-//     virtual void _setRowUpperBound(int i, Value value) = 0;
     virtual void _setRowBounds(int i, Value lower, Value upper) = 0;
     virtual void _getRowBounds(int i, Value &lower, Value &upper)=0;
 
@@ -795,7 +715,7 @@
     ///@{
 
     ///Add a new empty column (i.e a new variable) to the LP
-    Col addCol() { Col c; c.id=cols.insert(_addCol()); return c;}
+    Col addCol() { Col c; _addCol(); c.id = cols.addId(); return c;}
 
     ///\brief Adds several new columns
     ///(i.e a variables) at once
@@ -887,7 +807,7 @@
 
     ///This function adds a new empty row (i.e a new constraint) to the LP.
     ///\return The created row
-    Row addRow() { Row r; r.id=rows.insert(_addRow()); return r;}
+    Row addRow() { Row r; _addRow(); r.id = rows.addId(); return r;}
 
     ///\brief Add several new rows
     ///(i.e a constraints) at once
@@ -965,8 +885,6 @@
       e.simplify();
       _setRowCoeffs(_lpId(r), LpRowIterator(e.begin(), *this),
                     LpRowIterator(e.end(), *this));
-//       _setRowLowerBound(_lpId(r),l-e.constComp());
-//       _setRowUpperBound(_lpId(r),u-e.constComp());
        _setRowBounds(_lpId(r),l-e.constComp(),u-e.constComp());
     }
 
@@ -1008,7 +926,7 @@
     ///\todo Please check this
     void eraseCol(Col c) {
       _eraseCol(_lpId(c));
-      cols.erase(c.id);
+      cols.eraseId(c.id);
     }
     ///Erase a  row (i.e a constraint) from the LP
 
@@ -1016,7 +934,7 @@
     ///\todo Please check this
     void eraseRow(Row r) {
       _eraseRow(_lpId(r));
-      rows.erase(r.id);
+      rows.eraseId(r.id);
     }
 
     /// Get the name of a column
@@ -1216,31 +1134,14 @@
     }
 #endif
     
-//     /// Set the lower bound of a row (i.e a constraint)
-
-//     /// The lower bound of a linear expression (row) has to be given by an 
-//     /// extended number of type Value, i.e. a finite number of type 
-//     /// Value or -\ref INF.
-//     void rowLowerBound(Row r, Value value) {
-//       _setRowLowerBound(_lpId(r),value);
-//     };
-//     /// Set the upper bound of a row (i.e a constraint)
-
-//     /// The upper bound of a linear expression (row) has to be given by an 
-//     /// extended number of type Value, i.e. a finite number of type 
-//     /// Value or \ref INF.
-//     void rowUpperBound(Row r, Value value) {
-//       _setRowUpperBound(_lpId(r),value);
-//     };
 
     /// Set the lower and the upper bounds of a row (i.e a constraint)
 
-    /// The lower and the upper bound of
-    /// a constraint (row) have to be given by an 
-    /// extended number of type Value, i.e. a finite number of type 
-    /// Value, -\ref INF or \ref INF. There is no separate function for the 
-    /// lower and the upper bound because that would have been hard to implement 
-    /// for CPLEX.
+    /// The lower and the upper bound of a constraint (row) have to be
+    /// given by an extended number of type Value, i.e. a finite
+    /// number of type Value, -\ref INF or \ref INF. There is no
+    /// separate function for the lower and the upper bound because
+    /// that would have been hard to implement for CPLEX.
     void rowBounds(Row c, Value lower, Value upper) {
       _setRowBounds(_lpId(c),lower, upper);
     }