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evaluating divide and minus in correct order

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git-svn-id: svn://anubis/gvsu@116 45c1a28c-8058-47b2-ae61-ca45b979098e
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josh 2008-06-01 23:32:58 +00:00
parent d4c0c32b25
commit 6358a63af5
1 changed files with 20 additions and 17 deletions
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37
cs675/bottomup/jholtrop/gvsu/cs675/bottomup/Evaluator.java
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@ -6,7 +6,7 @@ import jholtrop.gvsu.cs675.bottomup.node.*;
import jholtrop.gvsu.cs675.bottomup.lexer.Lexer; import jholtrop.gvsu.cs675.bottomup.lexer.Lexer;
import jholtrop.gvsu.cs675.bottomup.parser.Parser; import jholtrop.gvsu.cs675.bottomup.parser.Parser;
import java.io.*; import java.io.*;
import java.util.HashMap; import java.util.Stack;
public class Evaluator extends DepthFirstAdapter public class Evaluator extends DepthFirstAdapter
{ {
@ -20,7 +20,9 @@ public class Evaluator extends DepthFirstAdapter
Start tree = p.parse(); Start tree = p.parse();
tree.apply(new Evaluator()); Evaluator e = new Evaluator();
tree.apply(e);
System.out.println("Result: " + e.getResult());
} }
catch (Exception e) catch (Exception e)
{ {
@ -28,38 +30,39 @@ public class Evaluator extends DepthFirstAdapter
} }
} }
private HashMap<Node, Double> m_exprValues = new HashMap<Node, Double>(); private Stack<Double> m_exprValues = new Stack<Double>();
private double getNumValue(TNumber num) public double getResult()
{ {
return Double.parseDouble(num.getText()); return m_exprValues.peek();
} }
public void outAAdditionExpr(AAdditionExpr e) public void outAAdditionExpr(AAdditionExpr e)
{ {
Double result = m_exprValues.push(m_exprValues.pop() + m_exprValues.pop());
m_exprValues.get(e.getExpr()) + m_exprValues.get(e.getTerm());
m_exprValues.put(e, new Double(result));
} }
public void outASubtractionExpr(ASubtractionExpr e) public void outASubtractionExpr(ASubtractionExpr e)
{ {
Double result = double b = m_exprValues.pop();
m_exprValues.get(e.getExpr()) - m_exprValues.get(e.getTerm()); double a = m_exprValues.pop();
m_exprValues.put(e, new Double(result)); m_exprValues.push(a - b);
} }
public void outAMultiplicationTerm(AMultiplicationTerm e) public void outAMultiplicationTerm(AMultiplicationTerm e)
{ {
Double result = m_exprValues.push(m_exprValues.pop() * m_exprValues.pop());
m_exprValues.get(e.getTerm()) * m_exprValues.get(e.getFactor());
m_exprValues.put(e, new Double(result));
} }
public void outADivisionTerm(ADivisionTerm e) public void outADivisionTerm(ADivisionTerm e)
{ {
Double result = double b = m_exprValues.pop();
m_exprValues.get(e.getTerm()) / m_exprValues.get(e.getFactor()); double a = m_exprValues.pop();
m_exprValues.put(e, new Double(result)); m_exprValues.push(a / b);
}
public void caseTNumber(TNumber n)
{
m_exprValues.push(Double.parseDouble(n.getText()));
} }
} }