Generating Non Repeatable Random No...

[LOSTBOY]

Hi Experts

   Am an PHP Beginner

 here i give snap of my code ..... there how can i generate non repeating random nos...............this code didnt  work properly what can i do for that

  do{  

 $qno=rand(1, $_SESSION['$max']);  

 if (!in_array($qno,$tempArray)){

   $_SESSION[$tempArray[$r]] = $qno;

$i=0;

$query="SELECT * FROM question WHERE qid='$qno' " ;

   $result=mysql_query($query);

   $id=mysql_result($result,$i,"qid");

   $question=mysql_result($result,$i,"question");

   mysql_result($result,$i,"question");

   $query1="SELECT * from answer where qid=$id";

   $result1=mysql_query($query1);

$r++ ;

 }

}while($r <= $n)

 

 

 

thanks in advance

[PHP_PhREEEk]

>what can i do for that

 

First, wrap code in code tags

 

[ code]code here[ /code]

(remove leading space after first bracket in each)

 

Second, format your code so that it's readable and the logic is present.

 

PhREEEk

[LOSTBOY]

thanks for ur valuable suggestion ..sorry ......am an newbie  to this forum....

  $r=0
  do{   
  $qno=rand(1, $_SESSION['$max']);   
  if (!in_array($qno,$tempArray)){ 
    $tempArray[$r] = $qno; 
    $query="SELECT * FROM question WHERE qid='$qno' " ;
    $result=mysql_query($query);
    $id=mysql_result($result,$i,"qid");
    $question=mysql_result($result,$i,"question");
    mysql_result($result,$i,"question");
    $query1="SELECT * from answer where qid=$id";
    $result1=mysql_query($query1);
    $r++ ;
  } 
}while($r <= $n)

[PHP_PhREEEk]

>sorry ......am an new one to this forum....

 

As we all were at one time.. no worries = )

 

<?php
  do{   
  $qno=rand(1, $_SESSION['$max']);   
  if (!in_array($qno,$tempArray)){ 
    $tempArray[$r] = $qno; 
     v$i=0;

 

v$i is not a valid PHP variable. Was that a typo?

Maybe you meant $i? or $vi?

 

Fix that and see where you are. If it doesn't work, tell us what error you recieve or what result you recieve that isn't what you are expecting.

 

PhREEEk

 

[LOSTBOY]

ya ...i have already cleared that error but still .....it gerating the repeated no

[~n[EO]n~]

And what will be your $_SESSION['$max'] maximum value, if it is low then there is max chance of repeating. Try using mt_rand instead. Not too sure but give a try 

$qno=mt_rand(1, $_SESSION['$max']); 

 

It looks like you are trying to fetch a random question from DB, if it is right then you can try ORDER BY RAND() in your select.

There is a sticky out there in MySQL board.

Hope it helps

[wsantos]

What do you mean repeating? This line would assure you that you have unique data in your $tempArray

 

if (!in_array($qno,$tempArray))

 

Which data is repeating?

[LOSTBOY]

$max is the Maximum question that user want to take....

[~n[EO]n~]

I think wsantos is right 

What does your $tempArray contains can you show it ?

[wsantos]

Anyway try this spaghetti code of mine

 

  do
  {   
    $qno=rand(1, $_SESSION['max']);   
    if (!in_array($qno,$tempArray)) 
      $tempArray[] = $qno; 
  }while(count($tempArray)<$_SESSION['max']);
//  This will ensure that all elements of tempArray is unique and has count equal to max

  for($i=0;$i<count($tempArray;$i++)
  {
      $query="SELECT q.qid,q.question,a.answer FROM question q JOIN answer a ON a.qid=a.qid WHERE qid=$tempArray[$i] " ;
      $result=mysql_query($query);
      $questionandanswer[]=mysql_fetch_row($result,MYSQL_ASSOC))
  }
// This will get all records of from your db with qid equal to the qids in your tempArray

[LOSTBOY]

thanks let me try ....

[LOSTBOY]

hi wsantos....

 

ur code works properly but it shows all the question & ans in single page..but i need to show one after another .....in the same page..wat can i do for that

[wsantos]

What do you mean one after another?

 

question 1 - answer 1

question 2 - answer 2

 

or

 

question 1

question 2

 

then

 

answer 1

answer 2

 

Paste your display snippet

[LOSTBOY]

actually am trying this project as quiz system.so i need to show only one set at a time.......

[wsantos]

In that case let's revise the last code I posted and since you are using sessions. Try this though I haven't tested this (working on imagination)

 

  $tempArray=$_SESSION['questionsandanswer'];  // Make sure you get the value for the array
  $flag=0;
do
  {   
    $qno=rand(1, $_SESSION['max']);   
    if (!in_array($qno,$tempArray)) 
    {
      $tempArray[] = $qno; 
      $flag = 1;  // Used this to indicate that a record is added
    }
  }while(count($tempArray)<$_SESSION['max'] && $flag=0);
//  This will ensure that all elements of tempArray is unique and has count equal to max
//  This will only add one record to your tempArray every call to this page

  $id=$tempArray[count($tempArray)-1];
  $query="SELECT q.qid,q.question,a.answer FROM question q JOIN answer a ON a.qid=a.qid WHERE qid=$tempArray[$id] " ;
  $result=mysql_query($query);
  $questionandanswer=mysql_fetch_row($result,MYSQL_ASSOC))
// This will get the last record of that tempArray
  $_SESSION['questionandanswer']=$tempArray;
// Make sure you pass the updated tempArray

 

Sorry for the spaghetti code guys...