PHP help

[xampi]

Hi guys,

I want to create a STRING that contains numbers from 1 to 10 without repetition. How can I do that? (This is what I have) (I'm very newbie in programming).

 

    <?php
        for($i=0;$i<=9;$i++){
            $rannumber='';
            $rannumber.= mt_rand(1, 10);
            print($rannumberi);
        }
    ?>

 

Edited October 29, 2020 by LogicalDrm

[Spotty]

Moved to Programming forum. 

[werto165]

11 minutes ago, xampi said:

Hi guys,

I want to create a STRING that contains numbers from 1 to 10 without repetition. How can I do that? (This is what I have) (I'm very newbie in programming).

 

    <?php

        for($i=0;$i<=9;$i++){

            $rannumber='';

            $rannumber.= mt_rand(1, 10);

            print($rannumberi);

        }

    ?>

not really familar with php so I'm kind guessing the syntax

   for($i=1;$i<=10;$i++){

            $rannumber='';

            $rannumber.=  $i;

            print($rannumber);

        }

Ignore me. terrible answer lol 

 

That what u want? 

 

$rannumber='';
  for($i=1;$i<=10;$i++){
            
            $rannumber.=  $i;
            
        }
print($rannumber);
 

[xampi]

6 minutes ago, werto165 said:

not really familar with php so I'm kind guessing the syntax

   for($i=1;$i<=10;$i++){

            $rannumber='';

            $rannumber.=  i;

            print($rannumber);

        }

Ignore me. terrible answer lol 

The thing is that I want numbers from 1 to 10 randomly generated with no repetitions.

 

I need them to be random, not from 1 to 10 thanks to $i but thanks for the help!

[werto165]

4 minutes ago, xampi said:

The thing is that I want numbers from 1 to 10 randomly generated with no repetitions.

 

Your syntax repeats numbers but thanks for the help!

a single string? if so you'll need a global scope for your variable. random isn't really random per se. from what I remember it takes the current time on ur CPU clock and from that passes it into a formula to give u a number. so a random number each time could be 11111111 not 12456 if that makes some sense. If you don't want them to repeat you will need to perform a check that those values aren't already used so if the first random number is 1 then that can't be used again for the random number. 

[homeap5]

Use array, populate it with numbers 1, 2, 3... and then replace first value in array with random value from array, then second with random etc.

[xampi]

1 minute ago, werto165 said:

a single string? if so you'll need a global scope for your variable. random isn't really random per se. from what I remember it takes the current time on ur CPU clock and from that passes it into a formula to give u a number. so a random number each time could be 11111111 not 12456 if that makes some sense. 

Look I have something more elaborated that doesn't work. I hope it helps you understand what i'm trying to get:

 

        // $numbers = '';
        // for($i=0;$i<=9;$i++){
        //     $rannumberi= '';
        //     $rannumber.= mt_rand(1, 10);
        //     // if(strstr($numbers, $rannumber) == FALSE) {
        //         print($numbers).'<br>';
        //         $numbers.= $rannumber;
        //     // }else{
        //         // $i = $i - 1;
        //     // }
        // }

[xampi]

2 minutes ago, homeap5 said:

Use array, populate it with numbers 1, 2, 3... and then replace first value in array with random value from array, then second with random etc.

I can't do it with any array. It's an exercice from school.

[werto165]

2 minutes ago, xampi said:

I can't do it with any array. It's an exercice from school.

if you can't use an array and need to use random you will have to use a while loop. A for loop will not work because it may run the same number twice and you wont get a string that's 11 characters long. 

[homeap5]

<?php
$r="0123456789";
for($t=0;$t<10;$t++){
$b=rand(0,9);
$v1=substr($r,$t,1);
$v2=substr($r,$b,1);
$r=substr_replace($r,$v1,$b,1);
$r=substr_replace($r,$v2,$t,1);
}
echo($r);
?>

Done, without array.

If all you need is numbers from 0 to 9 to be mixed in single text variable.

[pd.]

28 minutes ago, homeap5 said:

Done, without array.

If all you need is numbers from 0 to 9 to be mixed in single text variable.

If you want to confuse a newbie go for recursion with ternary. 

<?php
function recursiveRandomNumStr($n, $str = '') {
    return (0 === $n) ? $str : recursiveRandomNumStr(--$n, $str .= mt_rand(0, 9));
}
echo recursiveRandomNumStr(10);

 

1 hour ago, xampi said:

Hi guys,

I want to create a STRING that contains numbers from 1 to 10 without repetition. How can I do that? (This is what I have) (I'm very newbie in programming).

 

    <?php

        for($i=0;$i<=9;$i++){

            $rannumber='';

            $rannumber.= mt_rand(1, 10);

            print($rannumberi);

        }

    ?>

Your mistake is that you initialise rannumber and print it out inside the cycle

<?php
$rannumber='';
for($i=0;$i<=9;$i++){
    $rannumber.= mt_rand(0, 9);
} 
print($rannumber);

 

[homeap5]

22 minutes ago, pd. said:

If you want to confuse a newbie go for recursion with ternary.

I give a proper solution - all numbers must not repeat but being in random order.

Your example is not working like that.

OP Said: "I want to create a STRING that contains numbers from 1 to 10 without repetition."

I also understand that not so good as I see, because it's not 0 to 9, but that is not big difference - he may replace 0 with 10 in results and display every number in separate line. I think that is why OP start with empty string inside loop and print every number separately.

 

So, small fix for my code:

<?php
$r="0123456789";
for($t=0;$t<10;$t++){
$b=rand(0,9);
$v1=substr($r,$t,1);
$v2=substr($r,$b,1);
$r=substr_replace($r,$v1,$b,1);
$r=substr_replace($r,$v2,$t,1);
}

for($t=0;$t<10;$t++){
$rr=substr($r,$t,1);
if ($rr==0) $rr="10";
echo($rr."<br>");
}
?>

This will display all numbers from 1 to 10 in separate lines, in random order. And "0" is replaced by "10".

[pd.]

1 minute ago, Sakuriru said:

 

<?php

$array = [1, 2, 3, 4, 5, 6, 7, 8, 9, 10];
shuffle($array);

foreach($array as $n) {
    echo $n . "\n";
}

 

2 hours ago, xampi said:

I can't do it with any array. It's an exercice from school.

 

[pd.]

1 hour ago, Sakuriru said:

if the teacher wants to be pedantic

<?php
$start = 1;
$stop = 10;
for ($i = $start; $i <= $stop; $i++) {
    $$i = $i;
}
for ($i = $start; $i <= $stop; $i++) {
    $m = mt_rand($start, $stop);
    $tmp = ${$m};
    $$m = ${$i};
    $$i = $tmp;
}
for ($i = $start; $i <= $stop; $i++) {
    echo ${$i} . ' ';
}

No arrays, no string, works for any range

BTW, @xampi this is probably not the answer that your teacher expects. Even if it works, this is an ugly solution that basically uses variable variables as a subtitute for arrays.

Edited October 29, 2020 by pd.
Added warning

[xampi]

Ty so much guys for the help!