如何防止重複組合兩個隨機數字？

Question

這裏我的我的用於產生三個詞的組合（combo_generator.php）代碼：

<?php 

include "db_connect.php"; 

// Query database of words 
$words_sql = "SELECT * FROM words"; 
$words_res = mysqli_query($db, $words_sql)or die(mysqli_error()); 

// Create array of words 
$array = array(); 

// Loop through each word and add each to the array 
while($row = mysqli_fetch_array($words_res)){ 
    $array[] = $row['word']; 
} 

// Set $word1 as random word from $array 
$ran_num = array_rand($array); 
$word1 = $array[$ran_num]; 

// Remove the chosen word from the array 
array_splice($array, $ran_num, 1); 

// Reset the array 
$array2 = $array; 

// Set $word2 as random word from $array 
$ran_num2 = array_rand($array2); 
$word2 = $array2[$ran_num2]; 

// Set variables 
$word  = 'star'; 
$three_words = "$word.$word1.$word2"; 

echo $three_words; 

?> 

這是我的用於分配隨機三字組合從數據庫（test.php的）每個星號代碼：

<?php 

include "db_connect.php"; 

// Pull all stars from database 
$stars_sql = "SELECT * FROM stars"; 
$stars_res = mysqli_query($db, $stars_sql)or die(mysqli_error()); 

// Loop through every star in the array 
while($row = mysqli_fetch_array($stars_res)){ 
    // Store the star name in a variable 
    $star = $row['star_name']; 

    // Create a random 3-word combination 
    include "combo_generator.php"; 

    // Attach the random 3-word combination to the star 
    echo $star.'&nbsp;&nbsp;&nbsp;&nbsp;'.$three_words.'<br/><br/>'; 
} 

?> 

我試圖生成形式star.word1.word2，其中字詞1是從數據庫中隨機單詞，單詞2是從數據庫（字詞不同的隨機字三個詞組合！= WORD2）。然後將生成的每個組合分配給數據庫中的星形。

如何避免重複組合？通過重複組合，我的意思是：

組合1：star.lamp.chair;組合2：star.dog.ball;組合3：star.ball.dog;組合4：star.lamp.chair

在這裏，組合1和組合4是相同的 - 這種重複是我想要避免的。順序並不重要，所以組合2和組合3都很好。

Answer 1

您可以創建與所有可能的字對的數組，然後做拾刪除該數組：

<?php 

// Retrieve a list of words from the DB and build the pairs list 
include "db_connect.php"; 

// Query database of words 
$words_sql = "SELECT * FROM words"; 
$words_res = mysqli_query($db, $words_sql)or die(mysqli_error()); 

// Create array of words 
$array = array(); 

// Loop through each word and add each to the array 
while($row = mysqli_fetch_array($words_res)){ 
    $array[] = $row['word']; 
} 

// Create all valid pairs 
$pairs = array(); 
foreach ($array as $word1) { 
    foreach ($array as $word2) { 
     if ($word1 !== $word2) { 
      $pairs[] = "$word1.$word2"; 
     } 
    } 
} 

// Pull all stars from database 
$stars_sql = "SELECT * FROM stars"; 
$stars_res = mysqli_query($db, $stars_sql)or die(mysqli_error()); 

// Loop through every star in the array 
while($row = mysqli_fetch_array($stars_res)){ 
    // Store the star name in a variable 
    $star = $row['star_name']; 

    // Set $pair as random word from $pairs 
    $ran_num = array_rand($pairs); 
    $pair = $pairs[$ran_num]; 

    // ... and remove it 
    array_splice($pairs, $ran_num, 1); 

    // Set variables 
    $word  = 'star'; 
    $three_words = "$word.$pair"; 

    // Attach the random 3-word combination to the star 
    echo $star.'&nbsp;&nbsp;&nbsp;&nbsp;'.$three_words.'<br/><br/>'; 
} 

?> 

Answer 2

您可以保存已創建的組合。

創建一個全局數組（=在test.php的一個變量）代表所有已創建的組合：

/*@var $createdCombinations array*/ 
$createdCombinations=[]; 

然後，之前只是呼應你的新組合，檢查它是否已被創建。如果沒有，將它添加到數組中。如果是，則創建一個新組合。

像這樣：

// ... 

while(true){ 
    // Set $word1 as random word from $array 
    $ran_num = array_rand($array); 
    $word1 = $array[$ran_num]; 

    // ... 

    if(!in_array($three_words,$createdCombinations)){ 
     $createdCombinations[]=$three_words; 
     echo $three_words; 
     break; 
    } 
} 

代碼的其他部分可以保持不變，所以他們被省略。