随机乘法表生成器

Question

我在PHP中创建一个乘法表系统。

该系统的输入是表号和问题量。跳过表1，输入表2

在这一点上，我只是填充这样的数组：

$nCount = $_POST['count'];
$nHighest = $_POST['table'];
$aSums = [];
$nCounter = 0;
while($nCount > 0){
    $cSumString = rand(2, $nHighest) . "*" . rand(1, 10);
    $aSums[$nCounter] = $cSumString
    $nCount--;
    $nCounter++;
}

我想以多种方式解析问题：

3 * 5 = ... (normal)
... * 5 = 25 (first number to fill in)
8 * ... = 16 (second to fill in)

这需要随机化。

例：

1 * 2 = ... 
6 * ... = 12 
... * 4 = 20
8 * 4 = ...
2 * ... = 6

我唯一知道应该能够这样做这是一个开关，但我似乎无法让它正常工作，所以如果有人能给我一个正确的方向，我会很感激。我不是要求instacode只是一些提示会很棒。

Answer 1

$nCount = $_POST['count'];
$nHighest = $_POST['table'];
$aSums = [];
$leftOut = ['leftFactor', 'rightFactor', 'product'];

for ($i = 0; $i <= $nCount; $i++) {
  $leftOutRand = rand(0, count($leftOut) - 1);
  $factor = rand(1, $nHighest);
  $product = rand(0, $nHighest) * $factor;
  switch($leftOut[$leftOutRand]) {
    case 'leftFactor':
      $cSumString = '...' . ' * ' . $factor . ' = ' . $product;
      break;
    case 'rightFactor':
      $cSumString = $factor . ' * ' . '...' . ' = ' . $product;
      break;
    case 'product':
      $cSumString = rand(1, $nHighest) . ' * ' . rand(1, $nHighest) . ' = ' . '...';
      break;
  }
  $aSums[$i] = $cSumString;
}

示例输出：

2 * ... = 4
... * 2 = 6
1 * 1 = ...
... * 2 = 6
3 * ... = 12
2 * ... = 2
2 * 4 = ...
4 * ... = 0
3 * 1 = ...
2 * 1 = ...
... * 4 = 16
1 * ... = 2
... * 2 = 2
1 * 4 = ...
3 * ... = 9
2 * 3 = ...
2 * ... = 6
... * 1 = 3
... * 4 = 4
1 * 1 = ...
... * 3 = 9

Answer 2

<?php

$total = 4;
$table = 7;

$generate_pair = function() use ($table)
{
    $first = rand(1, 10);
    $last  = rand(2, $table);

    return [$first, $last];
};

$pairs = [];
while (count($pairs) < $total) {
    $pair = $generate_pair();
    if(!in_array($pair, $pairs))
        $pairs[] = $pair;
}

$questions = array_map(function ($v) {
    return sprintf('%d * %d', $v[0], $v[1]);
}, $pairs);

var_dump($questions);

示例输出：

array(4) {
  [0]=>
  string(5) "7 * 3"
  [1]=>
  string(5) "5 * 7"
  [2]=>
  string(5) "5 * 2"
  [3]=>
  string(5) "6 * 2"
}

Answer 3

我个人把它放在一个数组中并从那里读取它然后通过像Mark labenski提到的开关更容易得到它，我会这样做：

$questpertable = floor($questions / ($table-1));
$nTableCounter = 2; 
$array = [];
for ($nX = 0; $nX < ($table-1); $nX++){
  for ($nY = 0; $nY < $questpertable;){
      $left = rand(1, 10);
      $right  = $tablecounter;
      $answer = $left * $right;     
      $array[$nY] = array($left, $right, $answer );
      $Y++;                   
  }
  $tablecounter++;
}

唯一遗漏的是剩余价值，你必须找到一些东西来解决这个问题。