for ($i = 1; ; $i++)
{
    if ($i%5 == 1) {
        //第一个人取五分之一，还剩$t
        $t = $i - round($i/5) - 1;      
        if($t % 5 == 1)
        {
            //第二个人取五分之一，还剩$r
            $r = $t - round($t/5) - 1;      
            if($r % 5 == 1)
            {
                //第三个人取五分之一，还剩$s
                $s = $r - round($r/5) - 1;              
                if($s % 5 == 1)
                {
                    //第四个人取五分之一，还剩$x
                    $x = $s - round($s/5) - 1;                  
                    if($x % 5 == 1)
                    {
                        //第五个人取五分之一，还剩$y
                        $y = $x - round($x/5) - 1;                      
                        if ($y % 5 == 1) {
                            echo $i;
                            break;
                        }
                    }
                }
            }
        }
    }
}

function king($n, $m){
    $monkeys = range(1, $n);
    $i=0;
    $k=$n;
    while (count($monkeys)>1) {
        if(($i+1)%$m==0) {
            unset($monkeys[$i]);
        } else {
            array_push($monkeys,$monkeys[$i]);
            unset($monkeys[$i]);
        }
        $i++;
    }
    return current($monkeys);
}
 
$a = king(5, 2);
var_dump($a);

function hanoi($n,$x,$y,$z){
    if($n==1){
        echo 'move disk 1 from '.$x.' to '.$z."\n";
    }else{
        hanoi($n-1,$x,$z,$y);
        echo 'move disk '.$n.' from '.$x.' to '.$z."\n";
        hanoi($n-1,$y,$x,$z);
    }     
}
hanoi(3,'A','B','C');

//对数组冒泡排序
function bubble_sort($array){
    $count = count($array);
    if ($count <= 0) 
        return false;
        for($i=0; $i<$count; $i++){
            for($j=$count-1; $j>$i; $j–){
            if ($array[$j] < $array[$j-1]){
                $tmp = $array[$j];
                $array[$j] = $array[$j-1];
                $array[$j-1] = $tmp;
        }
    }
}
return $array;
}

function quick_sort($array) {
    if (count($array) <= 1) return $array;
    $key = $array[0];
    $left_arr = array();
    $right_arr = array();
    for ($i=1; $i<count($array); $i++){
 
    if ($array[$i] <= $key)
 
        $left_arr[] = $array[$i];
    else
        $right_arr[] = $array[$i];
    }
    $left_arr = quick_sort($left_arr);
    $right_arr = quick_sort($right_arr);
    return array_merge($left_arr, array($key), $right_arr);
}

//使用二分查找数组中某个元素
function bin_sch($array, $low, $high, $k){
    if ($low <= $high){
        $mid = intval(($low+$high)/2);
        if ($array[$mid] == $k){
            return $mid;
        }elseif ($k < $array[$mid]){
        return bin_sch($array, $low, $mid-1, $k);
    }else{
        return bin_sch($array, $mid+1, $high, $k);
    }
    }
    return -1;
}

function array_sort($arr, $keys, $order=0) {
    if (!is_array($arr)) {
        return false;
    }
    $keysvalue = array();
    foreach($arr as $key => $val) {
        $keysvalue[$key] = $val[$keys];
    }
    if($order == 0){
        asort($keysvalue);
    }else {
        arsort($keysvalue);
    }
    reset($keysvalue);
    foreach($keysvalue as $key => $vals) {
        $keysort[$key] = $key;
    }
    $new_array = array();
    foreach($keysort as $key => $val) {
        $new_array[$key] = $arr[$val];
    }
    return $new_array;
}