added ws202425 courses

2024_Praxis_der_Programmierung/ue12/loesung/List.java

@@ -0,0 +1,88 @@
+
+
+public class List<T>{
+	private ListElement<T> head; 
+
+	public List(ListElement<T> initLe){
+		head = initLe;
+	}
+
+	
+	public void insert(ListElement<T> newLe){
+		newLe.setNext(head);
+		this.head = newLe;
+	}
+
+	
+	public boolean delete(){
+		if (this.isEmpty()){
+			return false;
+		}
+		else {
+			this.head = head.getNext();
+			return true;
+		}
+	}
+
+
+	public boolean isEmpty(){
+		if (head == null){
+			return true;
+		}
+		else{
+			return false;
+		}
+	}
+
+	public int length(){
+		int count = 0;
+		
+		ListElement<T> curr = head;
+		while (curr != null){
+			count += 1;
+			curr = curr.getNext();
+		}
+		return count;
+	}
+
+	
+	public void show(){
+		ListElement<T> curr = head;
+		while (curr != null){
+			if (curr.getNext() == null){	
+				System.out.println(""+ curr.getValue());
+				}
+			else {
+				System.out.print(curr.getValue() + ", ");
+			}
+			curr = curr.getNext();
+		}
+	}
+
+
+	public boolean insertIndex(ListElement<T> newElem, int i) {	
+	  if (i == 0){
+		insert(newElem);
+		return true;
+	  }
+	  else {
+		ListElement<T> tmp = head;
+		ListElement<T> prev = null;
+		int l = 0;
+		// Aufsuchen des i-ten Elements
+		while (l < i) {
+		  prev = tmp;
+		  tmp = prev.getNext();
+		  l++;
+		  if (l > length()){
+			return false;
+		  }
+		} // l == i ist erreicht
+		prev.setNext(newElem);
+		newElem.setNext(tmp);
+		return true;
+    }
+}
+
+
+}

2024_Praxis_der_Programmierung/ue12/loesung/ListElement.java

@@ -0,0 +1,38 @@
+
+/*
+* class ListElement
+*
+*/
+
+public class ListElement<T>{
+	private T value;
+	private ListElement<T> next;
+
+	ListElement(T initValue){
+		this.value = initValue;
+		this.next = null;
+	}
+
+	ListElement(T initValue, ListElement<T> initNext){
+		this.value = initValue;
+		this.next = initNext;
+	}
+
+	public void setNext(ListElement<T> nextLe){
+		next = nextLe;
+	}
+
+	public ListElement<T> getNext(){
+		return this.next;
+	}
+
+	public void setValue(T newValue){
+		value = newValue;
+		
+	}
+
+	public T getValue(){
+		return this.value;
+	}
+
+}

2024_Praxis_der_Programmierung/ue12/loesung/ListIndexOutOfBoundsException.java

@@ -0,0 +1,11 @@
+
+public class ListIndexOutOfBoundsException extends IndexOutOfBoundsException{
+
+	int faulty_index;
+		
+	ListIndexOutOfBoundsException(){
+
+
+
+
+}

2024_Praxis_der_Programmierung/ue12/loesung/UseList.java

@@ -0,0 +1,54 @@
+
+import java.util.*;
+
+
+public class UseList {
+
+	public static void main(String [] args){
+		ListElement<Integer> le1 = new ListElement<Integer>(10, null);
+		List<Integer> list = new List<Integer>(le1);
+		ListElement<Integer> le2 = new ListElement<Integer>(20, null);
+		ListElement<Integer> le3 = new ListElement<Integer>(30, null);
+		ListElement<Integer> le4 = new ListElement<Integer>(40, null);
+
+		list.insert(le2);
+		list.insert(le3);
+
+		list.show();
+
+		//System.out.println("Laenge: " + list.length());
+		//list.delete();
+		//list.show();
+		
+		//list.insertIndex(le4, 1);
+		//list.show();
+		
+		Scanner scan = new Scanner(System.in);
+
+		while(true){
+			try{
+				System.out.print("Gebe eine positive Zahl ein: ");
+				int index = Integer.parseInt(scan.next());
+				list.insertIndex(le4, index);
+				list.show();
+				break;
+			}
+			
+			catch(NumberFormatException e){
+				System.err.println("Keine ganze Zahl eingegeben!");
+				continue;
+			}
+
+			catch(InputMismatchException e){
+				//bei parser nutzen
+				System.err.println("Keine ganze Zahl eingegeben!");
+				continue;
+			}
+
+			catch(NullPointerException e){
+				System.err.println("index blöd sein");
+				continue;
+			}
+		}
+	}
+}

2024_Praxis_der_Programmierung/ue12/loesung/insert.txt

@@ -0,0 +1,18 @@
+public void insert(ListElement<T> newElem, int i) {
+  if (i == 0)
+    insert(newElem);
+  else {
+    ListElement<T> tmp = head;
+    ListElement<T> prev = null;
+    int l = 0;
+    // Aufsuchen des i-ten Elements
+    while (l < i) {
+      prev = tmp;
+      tmp = prev.next;
+      l++;
+    } // l == i ist erreicht
+    prev.next = newElem;
+    newElem.next = tmp;
+  }
+}
+