Arrays homework 1-10

import java.util.Scanner;
public class Arrays_homework_1_10 {
    public static void main(String[] args) {

        Scanner sc = new Scanner(System.in);

        //Targil 1
        int[] arr1 = new int[10];
        System.out.println("Enter 10 numbers: ");
        for (int i = 0; i < arr1.length; i += 1) {
            arr1[i] = sc.nextInt();
        }
        System.out.println("It's numbers: ");
        for (int i = 0; i < arr1.length; i += 1) {
            if (arr1[i] % 2 == 0) {
                System.out.print(arr1[i] + " ");
            }
        }

        // Targil2
        char[] arr2 = new char[10];
        System.out.println("\nEnter 10 letters: ");
        for (int i = 0; i < arr2.length; i += 1) {
            arr2[i] = sc.next().charAt(0);
        }
        System.out.println("\nIndexes of Uppercase letters: ");
        for (int i = 0; i < arr2.length; i += 1) {
            if (arr2[i] >= 'A' && arr2[i] <= 'Z') { //בודק אם אות בתווך אותיות גדולות
                System.out.print(i + " ");
            }
        }

        //Targil 3
        int[] arr3 = new int[10];
        System.out.println("\nThird series: ");
        for (int i = 0; i < arr3.length; i += 1) {
            arr3[i] = i * 3; // מכפיל את הקאונטר של לולא ב 3 כך מיצר כפולות של 3 לפי סדר
            System.out.println(arr3[i] + " ");
        }

        //Targil 4
        int[] arr4 = new int[10];
        System.out.println("\nEnter 10 numbers: ");
        for (int i = 0; i < arr4.length; i += 1) {
            arr4[i] = sc.nextInt();
            if (i % 2 == 0) {
                arr4[i] += 1;
            }
        }
        for (int i = 0; i < arr4.length; i += 1) {
            System.out.println(arr4[i] + " ");
        }

        //Targil 5
        int[] arr5 = new int[10];
        System.out.println("Enter 10 numbers: ");
        for (int i = 0; i < arr5.length; i += 1) {
            arr5[i] = sc.nextInt();
            if (i % 2 == 0) {
                arr5[i] += 1;
            }
            if (i % 3 == 0) {
                arr5[i] -= 1;
            }
        }
        for (int i = 0; i < arr5.length; i += 1) {
            System.out.println(arr5[i] + " ");
        }

        //Targil 6
        char[] arr6 = new char[10];
        char ch;
        int counter = 0;
        System.out.println("Enter a letter: ");
        ch = sc.next().charAt(0);
        System.out.println("Enter 10 letters: ");
        for (int i = 0; i < arr6.length; i += 1) {
            arr6[i] = sc.next().charAt(0);
            if (ch == arr6[i]) {
                counter += 1;
            }
        }
        System.out.printf("The letter %c apears in the array %d times", ch, counter);

        //Targil 7
        int[] arr7 = new int[5], arr7_1 = new int[5];
        System.out.println("Enter 5 numbers for first array: ");
        for (int i = 0; i < arr7.length; i += 1) {
            arr7[i] = sc.nextInt();
        }
        System.out.println("Enter 5 numbers for second array: ");
        for (int i = 0; i < arr7_1.length; i += 1) {
            arr7_1[i] = sc.nextInt();
        }
        for (int i = 0; i < arr7.length; i += 1) {
            for (int j = 0; j < arr7_1.length; j += 1) {
                if (arr7[i] == arr7_1[j]) {
                    System.out.printf("A number at first array in the place %d the same whit number in second array at place %d\n", i, j);
                }
            }
        }

        //Targil 8
        int[] arr8 = new int[5], arr8_1 = new int[5], arr_sum = new int[5];
        System.out.println("Enter 5 numbers for first array: ");
        for (int i = 0; i < arr8.length; i += 1) {
            arr8[i] = sc.nextInt();
        }
        System.out.println("Enter 5 numbers for second array: ");
        for (int i = 0; i < arr8_1.length; i += 1) {
            arr8_1[i] = sc.nextInt();
        }
        for (int i = 0; i < arr_sum.length; i += 1) {
            arr_sum[i] = arr8[i] + arr8_1[i];
            System.out.print(arr_sum[i] + " ");
        }

        // Targil 9
        char[] arr9 = new char[5];
        String ifSame = "All letters are same";
        System.out.println("Enter 5 letters: ");
        for (int i = 0; i < arr9.length; i += 1) {
            arr9[i] = sc.next().charAt(0);
        }
        for (int i = 0; i < arr9.length - 1; i += 1) {
            if (arr9[i] != arr9[i + 1]) {
                ifSame = "Not all letters are same";
            }
        }
        System.out.println(ifSame);

        //Targil 10
        int[] arr10 = new int[5];
        String ifBigger = "All next number bigger than previous";
        System.out.println("Enter 5 numbers: ");
        for (int i = 0; i < arr10.length; i += 1) {
            arr10[i] = sc.nextInt();
        }
        for (int i = 0; i < arr10.length - 1; i += 1) {
            if (arr10[i] >= arr10[i + 1]) {
                ifBigger = "Not all next number bigger than previous";
            }
        }
        System.out.println(ifBigger);
    }
}