16.01.2025

.gitignore

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+*.class
+*.jar
+.devcontainer

src/de/dhbwka/java/exercise/datatypes/Round.java

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+package de.dhbwka.java.exercise.datatypes;
+
+class Round {
+    public static void main(String[] args) {
+        double pi = 3.1415926;
+        double e = 2.7182818;
+
+        int piInt = Round.round(pi);
+        int eInt = Round.round(e);
+
+        System.out.println("Pi: " + pi + " gerundet: " + piInt);
+        System.out.println("e: " + e + " gerundet: " + eInt);
+
+        int negativePiInt = Round.round(-pi);
+        int negativeEInt = Round.round(-e);
+
+        System.out.println("Pi: " + -pi + " gerundet: " + negativePiInt);
+        System.out.println("e: " + -e + " gerundet: " + negativeEInt);
+    }
+
+    private static int round(double number) {
+        return (int) (number % 1 >= 0.5 ? number + 1 : number % 1 <= -0.5 ? number - 1 : number);
+    }
+}

src/de/dhbwka/java/exercise/operators/Easter.java

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+package de.dhbwka.java.exercise.operators;
+
+public class Easter {
+  public static void main(String[] args) {
+    System.out.println("Jahr:");
+    java.util.Scanner scan = new java.util.Scanner(System.in);
+    int jahr = scan.nextInt();
+    scan.close();
+
+    int a = jahr % 19;
+    int b = jahr % 4;
+    int c = jahr % 7;
+    int k = jahr / 100;
+    int p = (8 * k + 13) / 25;
+    int q = k / 4;
+    int m = (15 + k - p - q) % 30;
+    int n = (4 + k - q) % 7;
+    int d = (19 * a + m) % 30;
+    int e = (2 * b + 4 * c + 6 * d + n) % 7;
+    int ostern = 22 + d + e;
+
+    if (ostern > 31) {
+      ostern -= 31;
+      System.out.println("Ostern: " + ostern + ". April " + jahr);
+    } else {
+      System.out.println("Ostern: " + ostern + ". März " + jahr);
+    }
+  }
+}

src/de/dhbwka/java/exercise/operators/IncrementDecrement.java

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+package de.dhbwka.java.exercise.operators;
+
+public class IncrementDecrement {
+  public static void main(String[] args) {
+    int i = 0; // i = 0
+    int j = 0; // j = 0
+    j = ++i; // j = 1, i = 1
+    int k = j++ + ++i; // k = 1 + 2 = 3, j = 2, i = 2
+    System.out.println("k: " + k); // k: 3
+    System.out.println("*: " + j++ + ++i); // *: 23
+    System.out.println(j++ + ++i); // 7
+    int m = j++ * ++i; // m = 5 * 4 = 21, j = 5, i = 5
+    System.out.println("m: " + m); // m: 20
+    int n = --j * --i; // n = 16, j = 4, i = 4
+    System.out.println("n: " + n); // n: 16
+    System.out.println("i: " + i); // i: 4
+    System.out.println("j: " + j); // j: 4
+  }
+}

src/de/dhbwka/java/exercise/operators/Priority.java

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+package de.dhbwka.java.exercise.operators;
+
+public class Priority {
+  public static void main(String[] args) {
+    System.out.println("1: " + (5 / 2 * 2)); // 1: 4
+    System.out.println("2: " + (9. / 2 * 5)); // 2: 22.5
+    boolean a = true, b = false, c = false;
+    System.out.println("3: " + (a && b || c)); // 3: false
+    char ch = 'c';
+    System.out.println("4: " + ('a' + 1 < ch)); // 4: true
+    int i = 1, j = 2, k = 3;
+    System.out.println("5: " + (-i - 5 * j >= k + 1)); // 5: false
+    i = 1;
+    if (a || (++i == 2)) {
+      System.out.println("6: " + i); // 6: 1
+    }
+    i = 1;
+    if (a | (++i == 2)) {
+      System.out.println("7: " + i); // 7: 2
+    }
+  }
+}