/**
 * A variable expression implements BooleanExp
 * A terminal expression
 */
import java.util.*;

public class VariableExp implements BooleanExp {
 private String name;
 
 public VariableExp(String _name) {
 name = _name;
 }

 public boolean Evaluate(Context c) {
 return c.LookUp(name);
 }

 public BooleanExp Copy() {
 return new VariableExp(name);
 }

 public BooleanExp Replace(String var, BooleanExp exp) {
 if(var.equals(name)) {
 return exp.Copy();
 } else {
 return new VariableExp(name);
 }
 }
 
}