Ensure no variables are equal (Lottery Code) - php

Question

So I am working on my Final Project for a web application development class I'm taking and I am creating a Powerball lottery generator. For this to work, the White ball numbers cannot be duplicated. Here is how my code is looking so far:
<?php
for($x = 1; $x < 6; $x++){
//set each white ball variable (a through e) to a random number between 1 and 69
$a = floor((lcg_value() * 69 + 1));
$b = floor((lcg_value() * 69 + 1));
$c = floor((lcg_value() * 69 + 1));
$d = floor((lcg_value() * 69 + 1));
$e = floor((lcg_value() * 69 + 1));
//set powerball number variable to a number between 1 and 26
$f = floor((lcg_value() * 26 + 1));
//echo all white ball numbers and powerball number
echo "<b><u>Set #" . $x . "</u></b> - <b>White ball numbers are: </b>" . $a . " , " . $b . " , " . $c . " , " . $d . " , " . $e . ". <b>Powerball Number is </b>" . $f . ".<br />";
};
?>
The issue with this code is that there is a chance that variables 'a' through 'e' have a chance of being duplicate numbers. What code could I use to ensure that none of the variables 'a' through 'e' are the same? I thought of doing something like:
if($a != $b || $a != $c || $a || $d...){
//echo numbers
}else{
//generate new numbers
};
But that is just too much work and I always try to find the most efficient ways to write code. I don't want to have to write more code than I need to. Any assistance would be greatly appreciated. Thank you in advance!

Answer 1

You could generate the numbers this way:
$arr = range(1, 69);
shuffle($arr);
$a = $arr[0];
$b = $arr[1];
$c = $arr[2];
$d = $arr[3];
$e = $arr[4];
Also take a look at Generating random numbers without repeats

Answer 2

Add them in an array and check for uniqueness:
<?php
for($x = 1; $x < 6; $x++){
$unique = false;
while(!$unique) {
//set each white ball variable (a through e) to a random number between 1 and 69
$a = floor((lcg_value() * 69 + 1));
$b = floor((lcg_value() * 69 + 1));
$c = floor((lcg_value() * 69 + 1));
$d = floor((lcg_value() * 69 + 1));
$e = floor((lcg_value() * 69 + 1));
$numbers = array($a, $b, $c, $d, $e);
if(count($numbers) == count(array_unique($numbers)) {
$unique = true;
}
}
//set powerball number variable to a number between 1 and 26
$f = floor((lcg_value() * 26 + 1));
//echo all white ball numbers and powerball number
echo "<b><u>Set #" . $x . "</u></b> - <b>White ball numbers are: </b>" . $a . " , " . $b . " , " . $c . " , " . $d . " , " . $e . ". <b>Powerball Number is </b>" . $f . ".<br />";
}

Answer 3

While loop the random generation of numbers and check for duplicates on the fly.
Test it here:
https://3v4l.org/odOqb
I have changed the random numbers to a smaller size to see if it does create duplicates.
But I have not seen any.
<?php
$arr =array();
for($x = 1; $x < 6; $x++){
//set each white ball variable (a through e) to a random number between 1 and 69
While (count($arr) != 5){
$arr[] = floor((lcg_value() * 6 + 1));
$arr = array_unique($arr);
}
//set powerball number variable to a number between 1 and 26
$f = floor((lcg_value() * 26 + 1));
Var_dump($arr);
//echo all white ball numbers and powerball number
//echo "<b><u>Set #" . $x . "</u></b> - <b>White ball numbers are: </b>" . $a . " , " . $b . " , " . $c . " , " . $d . " , " . $e . ". <b>Powerball Number is </b>" . $f . ".<br />";
};

Answer 4

To make it as efficient as possible you do not want to have to generate a new set of numbers each time therefore if a duplicate appears you would just want to re-pick for that letter right away.
To do this you can add the elements to an array and search through it after each letter to make sure its a unique number. This is done through the utilization of the for loop, while loop, and check variable.
<?php
for($x = 1; $x < 6; $x++) {
//set each white ball variable (a through e) to a random number between 1 and 69
$uniqueNumbers = array();
$check = true;
$a = floor((lcg_value() * 69 + 1));
array_push($uniqueNumbers, $a);
while ($check) {
$check = false;
$b = floor((lcg_value() * 69 + 1));
foreach ($uniqueNumbers as $element) {
if ($b == $element) {
$check = true;
}
}
}
array_push($uniqueNumbers, $b);
$check = true;
while ($check) {
$check = false;
$c = floor((lcg_value() * 69 + 1));
foreach ($uniqueNumbers as $element) {
if ($c == $element) {
$check = true;
}
}
}
array_push($uniqueNumbers, $c);
$check = true;
while ($check) {
$check = false;
$d = floor((lcg_value() * 69 + 1));
foreach ($uniqueNumbers as $element) {
if ($d == $element) {
$check = true;
}
}
}
array_push($uniqueNumbers, $d);
$check = true;
while ($check) {
$check = false;
$e = floor((lcg_value() * 69 + 1));
foreach ($uniqueNumbers as $element) {
if ($e == $element) {
$check = true;
}
}
}
array_push($uniqueNumbers, $e);
//set powerball number variable to a number between 1 and 26
$f = floor((lcg_value() * 26 + 1));
//echo all white ball numbers and powerball number
echo "<b><u>Set #" . $x . "</u></b> - <b>White ball numbers are: </b>" . $a . " , " . $b . " , " . $c . " , " . $d . " , " . $e . ". <b>Powerball Number is </b>" . $f . ".<br />";
}

Answer 5

Below code is for 6/49 Canada lottery
<body bgcolor="gold"><font size="9"></font>
<pre>
<?php
// Code by bhupinder Deol . modify according to needs
for ($i=0;$i<=10;$i++) {
for ($x=0;$x<=5;$x++) {
$rand[$x]=rand(1,49);
}
asort($rand);
$result = array_unique($rand);
$count = count($result);
if ($count == 6) {
print_r($rand);
$x=0;
}
else
{
echo "same numbers in array";
--$x;
}
}
?>
</pre>
</body>