From 24ea3fcd29983d5c2a7285efac0c4b049eb4f1c7 Mon Sep 17 00:00:00 2001
From: "f.mirabootalebi" <fat95378@gmail.com>
Date: Wed, 15 Apr 2026 17:37:31 +0000
Subject: [PATCH] Add HW01 exercises

---
 HW01/EvenSum_04.java      | 24 ++++++++++++++++++++++++
 HW01/Factorial_02.java    | 13 +++++++++++++
 HW01/HelloWorld_01.java   |  5 +++++
 HW01/Palindrome_03.java   | 26 ++++++++++++++++++++++++++
 HW01/PrimeFactors_05.java | 35 +++++++++++++++++++++++++++++++++++
 5 files changed, 103 insertions(+)
 create mode 100644 HW01/EvenSum_04.java
 create mode 100644 HW01/Factorial_02.java
 create mode 100644 HW01/HelloWorld_01.java
 create mode 100644 HW01/Palindrome_03.java
 create mode 100644 HW01/PrimeFactors_05.java

diff --git a/HW01/EvenSum_04.java b/HW01/EvenSum_04.java
new file mode 100644
index 0000000..2553d35
--- /dev/null
+++ b/HW01/EvenSum_04.java
@@ -0,0 +1,24 @@
+import java.util.ArrayList;
+public class EvenSum {
+
+    public static int sumEvenIndices(int[] array) {
+        ArrayList<Integer> list = new ArrayList<>();
+
+        for (int n : array) {
+            list.add(n);
+        }
+
+        int sum = 0;
+        for (int i = 0; i < list.size(); i++) {
+            if (i % 2 == 0) {
+                sum += list.get(i);
+            }
+        }
+        return sum;
+    }
+
+    public static void main(String[] args) {
+        int[] nums = {4, 7, 2, 9, 5};
+        System.out.println("Sum = " + sumEvenIndices(nums));
+    }
+}
\ No newline at end of file
diff --git a/HW01/Factorial_02.java b/HW01/Factorial_02.java
new file mode 100644
index 0000000..f0faa22
--- /dev/null
+++ b/HW01/Factorial_02.java
@@ -0,0 +1,13 @@
+import java.util.Scanner;
+public class Factorial{
+    public static void main(String[] args){
+        Scanner num = new Scanner(System.in);
+        long n = num.nextInt();
+        long result = 1;
+
+        for (int i=1 ; i <= n; i++){
+            result *= i;
+        }
+        System.out.println(n + "! = " + result);
+    }
+}
diff --git a/HW01/HelloWorld_01.java b/HW01/HelloWorld_01.java
new file mode 100644
index 0000000..3d781ec
--- /dev/null
+++ b/HW01/HelloWorld_01.java
@@ -0,0 +1,5 @@
+public class HelloWorld {
+    public static void main(String[] args) {
+        System.out.println("Hello, World!");
+    }
+}
\ No newline at end of file
diff --git a/HW01/Palindrome_03.java b/HW01/Palindrome_03.java
new file mode 100644
index 0000000..4349411
--- /dev/null
+++ b/HW01/Palindrome_03.java
@@ -0,0 +1,26 @@
+import java.util.Scanner;
+public class Palindrome {
+    static boolean isPalin(String s){
+        int i = 0;
+        int j = s.length()-1;
+
+        while (i < j) {
+            if (s.charAt(i) != s.charAt(j)){
+                return false;
+            }
+            i++;
+            j--;
+        }
+
+        return true;
+    }
+    public static void main(String[] args){
+
+    Scanner sc = new Scanner(System.in);
+    String str = sc.nextLine();
+
+    boolean isPal = isPalin(str);
+    System.out.println("is "+ str+ " palindrome? "+ isPal);
+
+    }
+}
diff --git a/HW01/PrimeFactors_05.java b/HW01/PrimeFactors_05.java
new file mode 100644
index 0000000..94bffbc
--- /dev/null
+++ b/HW01/PrimeFactors_05.java
@@ -0,0 +1,35 @@
+import java.util.Scanner;
+import java.util.ArrayList;
+
+public class PrimeFactors {
+    public static ArrayList<Integer> Factors(int num){
+        ArrayList<Integer>  factors = new ArrayList<>();
+
+        if (num <= 1){
+            System.out.println("no prime factor!.");
+        }
+
+        while (num%2 == 0){
+            factors.add(2);
+            num /= 2;
+        }
+        for(int i = 3; i*i <= num; i+=2){
+            while (num%i == 0){
+                factors.add(i);
+                num /= i;
+            }
+        }
+        if (num > 1 ){
+            factors.add(num);
+        }
+        return factors;
+    }
+    public static void main(String[] args){
+        Scanner sc = new Scanner(System.in);
+        int number = sc.nextInt();
+        ArrayList<Integer> factors = Factors(number);
+         if (!factors.isEmpty()){
+             System.out.println("factors =  "+ factors);
+         }
+    }
+}