Difference Between Break and Continue Statement

Difference between break and continue statement

break leaves a loop, continue jumps to the next iteration.

Difference between break and continue in PHP?

break ends a loop completely, continue just shortcuts the current iteration and moves on to the next iteration.

while ($foo) {   <--------------------┐
    continue;    --- goes back here --┘
    break;       ----- jumps here ----┐
}                                     |
                 <--------------------┘

This would be used like so:

while ($droid = searchDroids()) {
    if ($droid != $theDroidYoureLookingFor) {
        continue; // ..the search with the next droid
    }

    $foundDroidYoureLookingFor = true;
    break; // ..off the search
}

When to use break, and continue in C language?

Break,as the name suggests will break the execution of current loop once and for all while Continue will skip the execution of following statements and start new iteration.

It is known that loop may have it's termination condition, but sometimes it is possible that you achieve your goal before all the iteration has been executed (for example, consider best case scenario of Linear Search. It is possible that you found your element on 1st or 2nd iteration.)

In case of CONTINUE, sometimes it's possible that we need to skip some statement to get executed, but don't want to break the loop.
(For example as given in the link, the requirement is to sum the positive elements of array.In this case you need to skip negative elements, which can be achieved by Continue keyword.)

Yes, you can use them both with loop and without loop (for i.e in if..else or else..if ladder).

And yes, it is certainly a good practice to use them as both can save lot of execution time according to requirements.

For more info: Click here and here

Hope it will help!!

PHP - Difference between break and continue in switch case

Here is a simple example code with both the switch cases mentioned above

<?php
    $variable = 20;
    echo "Normal<br/>";
    switch ($variable) {
        case '20':
            echo "twenty";
        break;
        case '21':
            echo "twenty one";
        break;
    }

    echo "<br/><br/>With Continue<br/>";
    switch ($variable) {
        case '20':
            echo "twenty";
        continue;
        case '21':
            echo "twenty one";
        continue;
    }
?>

When I execute above code I got following output

Normal
twenty

With Continue
twenty

How?

Working of break statement

Break statement causes code execution to come out of the block and execute next statements because of which switch statement will execute only one case statement and exit out of switch block without executing other case blocks.

Working of Continue statement

Continue statement in case of loops will cause loop to stop execution of current iteration of loop and go for next iteration of the loop(if any exists) but in case of switch statement it is considered as a loop statement but no next iterations causing exit switch statement.

We can have a switch statement without break statements too like this

<?php
    $variable = 20;
    echo "Normal";
    switch ($variable) {
        case '19':
            echo "<br/>Nineteen";
        case '20':
            echo "<br/>twenty";
        case '21':
            echo "<br/>twenty one";
        case '23':
            echo "<br/>twenty three";
    }
?>

The output of above code will be

Normal
twenty
twenty one
twenty three

i.e. executing all the case statements after the case where first match is found.

Why is it necessary to use break and continue statements in Java while loops?

Why is it Necessary To Use “break” and “continue” Statements In Java
While Loops?

It doesn't.

You need to use break and continue only if your statements are not enough to cover the logic that you want to apply.

It doesn't mean that it is necessarily bad but sometimes, it is overused and the code could be simpler without it.

Look at your code for example.

1)The continue is helpless.

After the if statement, the loop goes on. It is exactly what does continue.
It would make sense if you had some statements after the else statement and you would not execute but it is not the case.

2) The break could also be removed.

You break because the while condition doesn't take into consideration end of loop.

While x < 21, x is incremented but as x keeps this value after, so
while (x <= 21){ will always be true.

So you have to find a way to exit from the block while to avoid an infinite loop.

You do so a break in the else.

You can write the same logic without break if the while condition handles the exit condition.

You can do it by introducing a boolean variable that provides a natural way to exit the loop when the expected age is reached :

int x = 0;
boolean isAgeReached = false;

while (!isAgeReached) {
    if (x < 21) {
      System.out.println("You cannot drink because you are only " + x + " years old.");
      x++;

    } 
     else {
       System.out.println("You may drink because you are " + x + " years old.");
       isAgeReached = true;
    }
}

Or still simpler :

int x = 0;
while (x < 21) {
    System.out.println("You cannot drink because you are only " + x + " years old.");
    x++;
}

System.out.println("You may drink because you are " + x + " years old.");

while (1) loop with continue and break statements

1. For infinite loop, you need to write while(true) instead of while(1).
2. If i % 2 != 0 is true, simply increment i by 1 and continue; otherwise, print the value of i and increment i by 1.

Demo:

public class Main {
    public static void main(String[] args) {
        int i = 1;
        while (true) {
            if (i % 2 != 0) {
                i++;
                continue;
            } else {
                writeToPage(i);
                i++;
            }

            if (i >= 20) {
                break;
            }
        }
    }

    static void writeToPage(int i) {
        System.out.println(i);
    }
}

Output:

2
4
6
8
10
12
14
16
18
20

Difference between Return and Break statements

break is used when you want to exit from the loop, while return is used to go back to the step where it was called or to stop further execution.

---

Related Topics