PHP Loop 1 to 10

Question

I need to make a loop in php that does 1 + 2 + 3 + 4 .... + 10 = 55 but icant get it to work. I did this:

<!DOCTYPE html>
<html>
<head>
    <title></title>
</head>
<body>
    <?php 
        for ($i = 1; $i <= 10; $i++){
            $sul = $i + $i + $i + $i + $i + $i + $i + $i + $i + $i;
            echo "$i + $i + $i + $i + $i + $i + $i + $i + $i + $i = $sul<br>";

        };

    ?>
</body>

Hope you can help me thanks :)

Possible duplicate of [Reference - What does this symbol mean in PHP?](http://stackoverflow.com/questions/3737139/reference-what-does-this-symbol-mean-in-php) — McNets, Nov 21 '16 at 09:15
@user7147407 you should try reading **[the manual](http://php.net/manual/en/control-structures.for.php)** which provides you with enough examples. — Franz Gleichmann, Nov 21 '16 at 09:18
Refer documentation here http://php.net/manual/en/control-structures.for.php — Thamaraiselvam, Nov 21 '16 at 09:20
@user7147407, If you need the answer like `1 + 2 + 3 + 4 + 5 + 6 + 7 + 8 + 9 + 10 = 55` Take a look at my answer. — Murad Hasan, Nov 21 '16 at 09:36
@user7147407, the accepted answer doesn't print your desired output. Kindly check my answer. Thanks! — Rav, Nov 21 '16 at 10:37

Karol Gasienica · Accepted Answer · 2016-11-21T11:36:54.120

This code should help you:

<?php
$sum = 0;
for($i = 1; $i<=10; $i++) {
    $sum = $sum + $i;
}
echo $sum;    
?>

You are incorrect using loop.

Explanation

I think it will be easier to understand with following table:

_____________________
|JUMP | $i   | $sum  |
|1    | 1    | 1     |
|2    | 2    | 3     |
|3    | 3    | 6     |
|4    | 4    | 10    |
|5    | 5    | 15    |
|6    | 6    | 21    |
|7    | 7    | 28    |
|8    | 8    | 36    |
|9    | 9    | 45    |
|10   | 10   | 55    |

More about for you can read in PHP: for

Update

If you want your structure it can be as follows:

<?php
$sum = 0;
$str = '';
for($i = 1; $i<=10; $i++) {
    $sum = $sum + $i;
    $str .= $i == 10 ? $i." = " : $i." + ";
}
echo $str.$sum;
?>

And it will output 1 + 2 + 3 + 4 + 5 + 6 + 7 + 8 + 9 + 10 = 55

score 7 · Answer 2 · answered Nov 21 '16 at 09:19

7

Something like this perhaps?

$range = range(1, 10);
$sum = array_sum($range);

echo implode(' + ', $range) . ' = ' . $sum;

range() - http://php.net/range

array_sum() - http://php.net/array_sum

implode() - http://php.net/implode

answered Nov 21 '16 at 09:19

Jonnix

4,121
1
30
31

Murad Hasan · Answer 3 · 2016-11-21T09:34:41.323

Just make a for loop from starting 1 to 10, like given below. You need to initialize the counter as 0 and while the loop executes you need to collect / sum them to the counter and finally outside the loop print/ echo the counter.

$count = 0;
$string = '';
for ($i = 1; $i <= 10; $i++){
    $count += $i;

    $string .= ($i == 10) ? $i : $i." + ";
}
echo $string." = ".$count; // 1 + 2 + 3 + 4 + 5 + 6 + 7 + 8 + 9 + 10 = 55

This is a very simple and straight forward way, you can do this using some array functions which is built-in in PHP.

Rav · Answer 4 · 2016-11-21T10:34:01.453

1

If you don't want to hardcode it, you can do this

<?php
$answer = 0;    
for ($i = 1; $i <= 10; $i++){
         $answer = $i + $answer;
         if ($i == 10) {
           echo $i." = ".$answer;
         }
         else {
           echo $i." + ";
         }       
    };
?>

Output is:

1 + 2 + 3 + 4 + 5 + 6 + 7 + 8 + 9 + 10 = 55

edited Nov 21 '16 at 10:34

answered Nov 21 '16 at 09:23

Rav

1,327
3
18
32

Notice: Undefined variable: answer in – Masivuye Cokile Nov 21 '16 at 09:27
@MasivuyeCokile, you downvoted my answer? Of course you have to initialize $answer = 0 before the loop. – Rav Nov 21 '16 at 10:13
@MasivuyeCokile, you should have realize that you should initialize the variable. SO is not an assignment-making website. – Rav Nov 21 '16 at 10:17
You should stated that when answering that the user needs to initialize answer, I know that I did not even run your code, but I knew there's a notice. You must remember when we answering we are also educating other people that might have the same problem in future. – Masivuye Cokile Nov 21 '16 at 10:23

score 0 · Answer 5 · answered Nov 21 '16 at 09:18

<!DOCTYPE html>
<html>
<head>
    <title></title>
</head>
<body>
    <?php
        $n = 10;
        $items = range(1, $n);
        $sum = array_sum($items);
        echo implode('+', $items) . ' = ' . $sum;
    ?>
</body>

This way is shorter. You generate the array from 1 to $n(10);

Then you calculate the sum of the items.

And then join each element with '+' and add the sum.

score 0 · Answer 6 · answered Nov 21 '16 at 09:22

0

There you go:

$sum = 0;
for($i = 1; $i <= 10; $i++){
    if($i == 10){
        echo $i;
    } else {
        echo $i." + ";
    }
    $sum = $sum + $i;
}
echo " = ".$sum;

answered Nov 21 '16 at 09:22

d3p4n5hu

411
4
9

score 0 · Answer 7 · answered Nov 21 '16 at 09:32

A for loop actually repeats a block of code n times, you syntax is right buy your semantic is wrong: initializes a counter in 0 and add i to the counter in each step as the other people say. Also, if is not compulsory to use a for, remember that the sum of first n natural numbers is n(n+1)/2, so no loop is actually needed

PHP Loop 1 to 10

7 Answers7