commit 494b70579ca2087babf25c478ff8aed6be31dcad
Author: haeslelu <haeslelu@localhost>
Date:   Mon Mar 21 12:45:38 2022 +0100

    Baum

diff --git a/Rechner/.classpath b/Rechner/.classpath
new file mode 100644
index 0000000..d54800d
--- /dev/null
+++ b/Rechner/.classpath
@@ -0,0 +1,10 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<classpath>
+	<classpathentry kind="con" path="org.eclipse.jdt.launching.JRE_CONTAINER/org.eclipse.jdt.internal.debug.ui.launcher.StandardVMType/JavaSE-11">
+		<attributes>
+			<attribute name="module" value="true"/>
+		</attributes>
+	</classpathentry>
+	<classpathentry kind="src" path="src"/>
+	<classpathentry kind="output" path="bin"/>
+</classpath>
diff --git a/Rechner/.gitignore b/Rechner/.gitignore
new file mode 100644
index 0000000..ae3c172
--- /dev/null
+++ b/Rechner/.gitignore
@@ -0,0 +1 @@
+/bin/
diff --git a/Rechner/.project b/Rechner/.project
new file mode 100644
index 0000000..0f3914b
--- /dev/null
+++ b/Rechner/.project
@@ -0,0 +1,17 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<projectDescription>
+	<name>Rechner</name>
+	<comment></comment>
+	<projects>
+	</projects>
+	<buildSpec>
+		<buildCommand>
+			<name>org.eclipse.jdt.core.javabuilder</name>
+			<arguments>
+			</arguments>
+		</buildCommand>
+	</buildSpec>
+	<natures>
+		<nature>org.eclipse.jdt.core.javanature</nature>
+	</natures>
+</projectDescription>
diff --git a/Rechner/.settings/org.eclipse.jdt.core.prefs b/Rechner/.settings/org.eclipse.jdt.core.prefs
new file mode 100644
index 0000000..f2525a8
--- /dev/null
+++ b/Rechner/.settings/org.eclipse.jdt.core.prefs
@@ -0,0 +1,14 @@
+eclipse.preferences.version=1
+org.eclipse.jdt.core.compiler.codegen.inlineJsrBytecode=enabled
+org.eclipse.jdt.core.compiler.codegen.targetPlatform=11
+org.eclipse.jdt.core.compiler.codegen.unusedLocal=preserve
+org.eclipse.jdt.core.compiler.compliance=11
+org.eclipse.jdt.core.compiler.debug.lineNumber=generate
+org.eclipse.jdt.core.compiler.debug.localVariable=generate
+org.eclipse.jdt.core.compiler.debug.sourceFile=generate
+org.eclipse.jdt.core.compiler.problem.assertIdentifier=error
+org.eclipse.jdt.core.compiler.problem.enablePreviewFeatures=disabled
+org.eclipse.jdt.core.compiler.problem.enumIdentifier=error
+org.eclipse.jdt.core.compiler.problem.reportPreviewFeatures=warning
+org.eclipse.jdt.core.compiler.release=enabled
+org.eclipse.jdt.core.compiler.source=11
diff --git a/Rechner/src/Calculator.java b/Rechner/src/Calculator.java
new file mode 100644
index 0000000..db102b2
--- /dev/null
+++ b/Rechner/src/Calculator.java
@@ -0,0 +1,71 @@
+
+public class Calculator {
+	public Node <Symbol> erzeugeBeispielBaum() {
+		Node<Symbol> root = new Node <Symbol>(new Symbol ("*"));
+		root.left = new Node<Symbol>(new Symbol("3"));
+		root.right = new Node<Symbol>(new Symbol("+"));
+		root.right.left = new Node <Symbol> (new Symbol ("5"));
+		root.right.right = new Node <Symbol> (new Symbol ("8"));
+		
+		return root;
+		
+	}
+ public int berechne(Node<Symbol> n) {
+	 if(n.left == null) {
+		 return n.content.getInt();
+	 }
+	 else {
+		 int links = berechne(n.left);
+		 int rechts = berechne(n.right);
+		  if(n.content.istMal() ) {
+			  return links* rechts;
+		  } else {
+			  return links + rechts;
+		  }
+	 }
+ }
+ public void infixAusgeben(Node <Symbol> n) {
+	 
+	 // wenn Blatt(also letztes)
+	if( n.left == null) {
+		System.out.print( n.content);    // wenn keine toString-Methode in Symbo Klasse dann n.content.getInt();
+	}
+	else {
+		 // links ausgeben
+		if(n.content.istMal() && n.left.content.istPlus() ) {
+			System.out.print("(");
+			infixAusgeben(n.left);
+			System.out.print(")");
+		}
+		else {
+		infixAusgeben(n.left);
+		}
+
+		// Operator ausgeben
+											//	if( n.content.istMal() ) {
+		System.out.print(n.content);     //	System.out.println("*");
+								 		  //	} else {
+							     		 //		System.out.println("+"); }
+			
+		// rechts ausgeben
+		// wenn aktuell ein * und rechts ein + dann mit Klammern
+		
+		if(n.content.istMal() && n.right.content.istPlus() ) {
+			System.out.print("(");
+			infixAusgeben(n.right);
+			System.out.print(")");
+		}
+		else {
+		infixAusgeben(n.right);
+		}
+ 
+
+	}
+
+ }
+
+
+}
+	 
+ 
+
diff --git a/Rechner/src/Node.java b/Rechner/src/Node.java
new file mode 100644
index 0000000..945cac8
--- /dev/null
+++ b/Rechner/src/Node.java
@@ -0,0 +1,12 @@
+
+public class Node <T>  {
+	
+	public T content;
+	public Node<T> left , right;
+
+	public Node(T zahl) {
+		this.content = zahl;
+		left = null;
+		right = null;
+	}
+}
diff --git a/Rechner/src/Symbol.java b/Rechner/src/Symbol.java
new file mode 100644
index 0000000..183f563
--- /dev/null
+++ b/Rechner/src/Symbol.java
@@ -0,0 +1,38 @@
+
+public class Symbol {
+	private String s;
+	
+	public Symbol(String _s) {
+		this.s = _s;
+	}
+
+	public boolean istMal() {
+		if(this.s == "*") return true;  // oder  return s == "*" ;
+		return false;
+	}
+	
+	public boolean istPlus() {
+	 return s == "+";
+	}
+	
+	public boolean istOperator() {
+		return istPlus() || istMal() ;
+	}
+	
+	public boolean istZahl() {
+		
+		if(!istOperator()) return true;
+		return false;
+	}
+	
+	public int getInt() {
+		
+		if( istZahl() == true) return Integer.parseInt(s);
+		return 0;
+		
+	}
+	
+	public String toString() {
+		return s;
+	}
+}
diff --git a/Rechner/src/Test.java b/Rechner/src/Test.java
new file mode 100644
index 0000000..bab21c3
--- /dev/null
+++ b/Rechner/src/Test.java
@@ -0,0 +1,14 @@
+
+public class Test {
+	public static void main(String[] args) {
+		
+		Calculator c = new Calculator();
+		
+		Node<Symbol> root = c.erzeugeBeispielBaum();
+		int ergebnis = c.berechne(root);
+		System.out.println(ergebnis);
+		
+		c.infixAusgeben(root);
+	}
+
+}