Conditional operators

A lecture snippet with a mentor as part of the Codegym University course. Sign up for the full course.

"Hi, Amigo. Today we'll talk about if/else statements."

"Programs would be of little use if they didn't respond to changing external circumstances. A program needs to know how to adapt to circumstances and perform one action in one case and other actions in other cases. In Java, this is achieved using the 'if/else statement' – a special construct that makes it possible to perform different code blocks if a condition is satisfied."

"It consists of three parts: 'condition', 'command 1' and 'command 2'. If the condition is true, then 'command 1' is executed, otherwise 'command 2' is executed. These commands are never both executed. The statement looks more or less like this:"

if (condition)
    command_1;
else
    command_2;

"How exciting! I think that statement will make programming much more interesting!"

"Yep. Here are a couple of examples for you:"

if (a < b)
    System.out.println("A is less than B");
else
    System.out.println("B is less than  A");

if (a < b)
{
    System.out.println("A is less than B");
    System.out.println("B is greater than A");
}
else
{
     System.out.println("B is less than A");
     System.out.println("A is greater than B");
}

if (a < b)
{
    a = 0;
}
else
{
}

if (a < b)
{
    a = 0;
}

if (a < b)
    a = 0;

"Diego just asked me to give you a few tasks."

4

Task

New Java Syntax, level 4, lesson 4

Locked

10 numbers

Display the numbers from 1 to 10 using a while loop. Each value should be on a new line.

Open

4

Task

New Java Syntax, level 4, lesson 4

Locked

From 10 to 1

Display the numbers from 10 to 1 using a while loop. Each value should be on a new line.

Open

4

Task

New Java Syntax, level 4, lesson 4

Locked

You can't have too much of a good thing

Use the keyboard to enter a string and a number N greater than 0. Use a while loop to display the string N times. Each value should be on a new line. Example input: abc 2 Example output: abc abc

Open

4

Task

New Java Syntax, level 4, lesson 4

Locked

Seeing dollars in your future

Use a while loop to display a 10x10 square of dollar signs. Don't separate the symbols in each line. Example output: $$$$$$ $$$$$ $$$$$ $$$$$ $$$$$ $$$$$ $$$$$ $$$$$ $$$$$ $$$$$

Open

A lecture snippet with a mentor as part of the Codegym University course. Sign up for the full course.