code: package gprover;
  
  /**
   * Created by IntelliJ IDEA.
   * User: yezheng
   * Date: 2006-5-4
   * Time: 11:32:50
   * To change this template use File | Settings | File Templates.
   */
  public class xterm {
      public var var;                //   variable.
      long c;                 //   value is an Integer.
      dterm ps;              //  prefix
      xterm p;                //
      String sd;
  
      public xterm() {
          var = null;
          c = 0;
          ps = null;
          p = null;
      }
  
      public long getPV() {
          if (ps == null || ps.p == null) return 0;
          return ps.p.c;
      }
  
      public String toString() {
          return sd;
      }
  
      public void cutMark() {
          if (sd != null && sd.trim().startsWith("+"))
              sd = sd.trim().substring(1);
      }
  
      public String getString() {
          if (sd == null) return null;
          String t = sd.trim();
          if (t.startsWith("+"))
              return t.substring(1).trim();
          return t;
      }
  
      public int getTermNumber() {
          xterm t = this;
          int n = 0;
          while (t != null) {
              dterm d = t.ps;
              if (d == null || d.nx == null) return n;
              t = d.nx.p;
              n++;
          }
          return n;
      }
  }
  