<?php

$arr1=array(2,5,7,9,12);

$arr2=array(3,4,6,8,10,11);

function merge_sort($arr1,$arr2){

    $len1=count($arr1);

    $len2=count($arr2);

    $arr=array();

    $i=$j=0;

    while($i<$len1&&$j<$len2){

        if($arr1[$i]<=$arr2[$j]){

            $arr[]=$arr1[$i++];

        }else{

            $arr[]=$arr2[$j++];

        }

    }

    while($i<$len1)

        $arr[]=$arr1[$i++];

    while($j<$len2)

        $arr[]=$arr2[$j++];

    return $arr;

}

print_r(merge_sort($arr1,$arr2));

function tento26($num){

    $str='';

    $chu=floor($num/26);

    $yu=$num%26;

    $str.="{".$yu."}";

    if($chu>26){

        $str.=tento26($chu);

    }else{

        $str.="{".$chu."}";

    }

    return $str;

}

function numtoalph($match){

    $alp=' abcdefghijklmnopqrstuvwxyz';

    if($match[1]>=26){

        return false;

    }

    return $alp[$match[1]];

}

$str= tento26(300);

$str1=strrev(preg_replace_callback('#\{(\d+)\}#','numtoalph',$str));

echo $str1;

<?php

function myjson_encode($arr){

    $jsonstr='{';

    foreach($arr as $k=>$v){

        if(is_array($v)){

            $jsonstr.='"'.$k.'":'.myjson_encode($v).',';

        }else{

            $jsonstr.='"'.$k.'":"'.$v.'",';

        }

    }

    $jsonstr=trim($jsonstr,',');

    $jsonstr.='}';

    return $jsonstr;

}

<?php

    #二分查找

    function binarySearch(Array $arr, $target) {

        $low = 0;

        $high = count($arr) - 1;

        while($low <= $high) {

            $mid = floor(($low + $high) / 2);

            #找到元素

            if($arr[$mid] == $target) return $mid;

            #中元素比目标大,查找左部

            if($arr[$mid] > $target) $high = $mid - 1;

            #重元素比目标小,查找右部

            if($arr[$mid] < $target) $low = $mid + 1;

        }

        #查找失败

        return false;

    }

    $arr = array(1, 3, 5, 7, 9, 11);

    $inx = binarySearch($arr, 1);

    var_dump($inx);

?>

<?php

error_reporting(0);

function cny($ns) {

    static $cnums=array("零","壹","贰","叁","肆","伍","陆","柒","捌","玖"),

    $cnyunits=array("圆","角","分"),

    $grees=array("拾","佰","仟","万","拾","佰","仟","亿");

    list($ns1,$ns2)=explode(".",$ns,2);

    $ns2=array_filter(array($ns2[1],$ns2[0]));

    $ret=array_merge($ns2,array(implode("",_cny_map_unit(str_split($ns1),$grees)),""));

    $ret=implode("",array_reverse(_cny_map_unit($ret,$cnyunits)));

    echo $ret;

    echo "<br>";

    return str_replace(array_keys($cnums),$cnums,$ret);

}

function _cny_map_unit($list,$units) {

    $ul=count($units);

    $xs=array();

    foreach (array_reverse($list) as $x) {

        $l=count($xs);

        if ($x!="0" || !($l%4)){

            $n=($x=='0'?'':$x).($units[($l-1)%$ul]);

        } else{

            $n=is_numeric($xs[0][0])?$x:'';

        }

        array_unshift($xs,$n);

    }

    return $xs;

}

echo cny(2305.32);

<?php

function ysf($arr,$current=0,$out=3){

    $count=count($arr);

    $num=1;

    if($count==1){

        echo $arr[0];

    }else{

        while($num++<$out){

            $current++;

            $current=$current%$count;

        }

        echo $arr[$current]."<br>";

        array_splice($arr,$current,1);

        ysf($arr,$current,$out);

    }

}

$arr=[1,2,3,4,5,6,7,8,9,10];

ysf($arr,0,4);