PHP Script to do exam.

exam.php

#!/usr/bin/php
<?php
/* Contents of exam.csv file like this:
奈奎斯特定理是哪一年提出来的？,1928
已知无线电频率为1GHz，其波长为（单位为m）：,0.3
已知WiFi的频率为2.4GHz，其波长为（单位为m）：,0.125
已知WiFi的频率为5GHz，其波长为（单位为cm）：,6
......
*/

$array = file('exam.csv');
foreach ($array as $string) {
    $pieces = explode(',', $string);
    $terms[$pieces[0]] = trim($pieces[1]);
}
// var_dump($terms);die();

system("clear");
$name = readline("Input Your Exam Name（Like: 04-张三）: ");
system("date");
$time_start = time();
$count = count($terms);

echo PHP_EOL;
echo "Hello, $name!";
echo PHP_EOL;
$line = "Init";
$i = 0;

// while ($term = current($terms)
    // $key = key($terms);
while (! empty($terms) && $key = array_rand($terms)) {
    $term = $terms[$key];
    $i++;
    while ($line !== $term) {
        if ($line !== "Init") {
            echo "Wrong! Try again!" . PHP_EOL;
        }
        $line = readline("$i/$count. $key: ");
    }
    echo "Good!";
    $line = "Init";
    echo PHP_EOL;
    readline("Press any key to continue ...");

    // next($terms);
    unset($terms[$key]);

    // If answer is right, clear the screen.
    system("clear");
    
    // Display $name on top.
    echo $name;
    echo PHP_EOL;
    echo PHP_EOL;
}

system("date");
$time_end = time();
echo PHP_EOL;
$seconds = $time_end - $time_start;
echo "$name, you finished the exam in " . $seconds . " seconds!";
echo PHP_EOL;

$content = "$name:$count: $seconds seconds, " . date('Y-m-d H:i:s', $time_start) . ', ' . date('Y-m-d H:i:s', $time_end) . "\n";
file_put_contents('./' . basename(__FILE__, '.php') . '.log', $content, FILE_APPEND | LOCK_EX);

while (true) { readline(); }