Java Taskbook Level 2.2

Задание 1

Find the arithmetic mean of all integers from 1 to 100.

Задание 2

Given a number:

javaint num = 12345;

Find the sum of the first and last digits of this number.

Задание 3

Given an array of integers:

javaint[] arr = {1, 2, 3, 4, 5};

Find the sum of the elements of this array.

Задание 4

Given some integer:

javaint num = 12345;

Output all its digits from the end to the console.