


Your favorite puzzle: Use PHP to print the nine-square grid - third-order magic square_PHP tutorial
ignore_user_abort(true);
set_time_limit(0);
$tmp = array();
function getArr($arr='')
{
for ($i = 1; $i
if ( empty($arr) ) {
$arr[] = $i;
} elseif ( in_array($i, $arr) ) {
continue;
} else {
$arr[] = $i;
}
if ( count($arr)
getArr($arr);
}
if ( count($arr) 1 ) {
array_pop($arr);
continue;
} elseif ( count($arr) == 1 ) {
unset($arr);
continue;
} elseif ( checkArr($arr) ) {
$GLOBALS['tmp'][] = $arr;
}
}
}
function checkArr($arr)
{
$m = array();
$m[] = $arr[0] + $arr[1] + $arr[2];
$m[] = $arr[3] + $arr[4] + $arr[5];
$m[] = $arr[6] + $arr[7] + $arr[8];
$m[] = $arr[0] + $arr[3] + $arr[6];
$m[] = $arr[1] + $arr[4] + $arr[7];
$m[] = $arr[2] + $arr[5] + $arr[8];
$m[] = $arr[0] + $arr[4] + $arr[8];
$m[] = $arr[2] + $arr[4] + $arr[6];
$tmp = array_count_values($m);
foreach ($tmp as $v) {
if ( $v == 8 ) {
return true;
} else {
return false;
}
}
}
$startTime = microtime(true);
getArr();
$endTime = microtime(true);
for( $i=0; $i
echo $str=
{$arr[0]} | {$arr[1]} | {$arr[2]} |
{$arr[3]} | {$arr[4]} | {$arr[5]} |
{$arr[6]} | {$arr[7]} | {$arr[8]} |
fs;
}
echo '
共花费时间:';
echo round($endTime - $startTime, 3);
echo '秒
';www.2cto.comdie;
用穷举的方式完成的,8个结果
我的电脑大约要花10.5秒种时间
用递归的方式完成,可以很方便的增加到4阶、5阶……
花了20分种写出来的,如果把不可能条件排除的话应该不用一秒钟就可以完成的
你们最喜欢的智力题
作者:zdrjlamp

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