Add RemoveStars and ComplexNumberMultiply string algorithms

Author: SYEDMDSAAD

src/main/java/com/thealgorithms/strings/ComplexNumberMultiply.java

@@ -0,0 +1,35 @@
+package com.thealgorithms.strings;
+
+/**
+ * Multiplies two complex numbers represented as strings in the form "a+bi".
+ *
+ * Example:
+ * Input: 1+1i , 1+1i
+ * Output: 0+2i
+ */
+public final class ComplexNumberMultiply {
+
+    private ComplexNumberMultiply() {
+    }
+
+    private static int[] parse(String num) {
+        String[] parts = num.split("\\+");
+        int real = Integer.parseInt(parts[0]);
+        int imaginary = Integer.parseInt(parts[1].replace("i", ""));
+        return new int[] {real, imaginary};
+    }
+
+    public static String multiply(String num1, String num2) {
+        int[] a = parse(num1);
+        int[] b = parse(num2);
+
+        int real = a[0] * b[0] - a[1] * b[1];
+        int imaginary = a[0] * b[1] + a[1] * b[0];
+
+        return real + "+" + imaginary + "i";
+    }
+
+    public static void main(String[] args) {
+        System.out.println(multiply("1+1i", "1+1i"));
+    }
+}

src/main/java/com/thealgorithms/strings/RemoveStars.java

@@ -12,12 +12,11 @@
 public final class RemoveStars {
 
     private RemoveStars() {
-        // Private constructor to prevent instantiation(object creation)
     }
 
     public static String removeStars(String s) {
         StringBuilder result = new StringBuilder();
-         
+
         for (char c : s.toCharArray()) {
             if (c == '*') {
                 if (result.length() > 0) {