1.寫函數創建長度為10的數組，數組中的元素為遞增的奇數，首項為1.

function createArr($first,$length){
for($i=$first;$i<=$length;$i++){
$num = 2*$i-1;
$arr[] = $num;
}
return $arr;
}
print_r(createArr(1,10));

2.創建長度為10的數組，數組中的數為遞增的等比數，比值為3，首項為1.

function createArr($ratio,$length){
$num = 1/$ratio;
for($i=1;$i<=$length;$i++){
$num = $num*$ratio;
$arr[] = $num;
}
return $arr;
}
print_r(createArr(3,10));

3.求數組中最大數的下標.

function maxkey($arr){
$maxval = max($arr);
foreach($arr as $key=>$val){
if($maxval == $val){
$maxkey = $key;
}
}
return $maxkey;
}


$arr = array(0,-1,-2,5,15,3);
echo maxkey($arr);

4.創建一個長度為10的數組，數組中的元素滿足斐波拉契數列的規律.

function arrFibo($n){
for($i=0;$i<$n;$i++){
if($i<2){
$arr[$i] = 1;
}else{
$arr[$i] = $arr[$i-1] + $arr[$i-2];
}
}
return $arr;
}
print_r(arrFibo(8));

5.寫一個方法，將一個長度超過10的數組最後5項直接截取，不改變順序變為前5項，如{1,2,3,4,5,6,7,8,9,10}變為{6,7,8,9,10,1,2,3,4,5}.

function arrsort($arr){
$num = count($arr);
if($num > 10){
//array_slice($arr,起始位置,截取長度,保留索引(默認為false))
$arr_firstpart = array_slice($arr,0,$num-5,true);
$arr_lastpart = array_slice($arr,($num-5),5,true);
}else{

echo "數組不超過10個元素,請重新輸入";
exit();
}
//拼接
$arr_new = array_merge($arr_lastpart,$arr_firstpart);
return $arr_new;
}
$arr = array("a"=>1,2,3,8,9,6,"b"=>5,-1,"c"=>8,0,7);
echo "<pre>";
print_r($arr);
echo "<br>= = = = = 拼接後 = = = = <br><br>";
print_r(arrsort($arr));
echo "</pre>";6.將兩個數組連接成一個新數組. $arr = array("a"=>1,"b"=>2,3);
$arr2 = array("a"=>Dee,3,5);
$arr3 = array_merge($arr,$arr2);
$arr4 = array_merge_recursive($arr,$arr2);
echo "<pre>";
print_r($arr3);
echo "<br> = = = = = <br><br>";
print_r($arr4);
echo "</pre>";

7.將兩個數組連成一個新數組

$arr = array("a"=>1,"b"=>2,3);
$arr2 = array("a"=>"zou",3,5);
$arr3 = array_merge($arr,$arr2);
$arr4 = array_merge_recursive($arr,$arr2);
echo "<pre>";
print_r($arr3);
echo "<br> = = = = = <br><br>";
print_r($arr4);
echo "</pre>";

8.數組逆序( 不能使用rsort函數，不能生成新數組 )

$arr = array("a","b","c",1,10);
$i = "";//要替換位置的數的下標
$j = "";//臨時變量
$k = "";//被替換位置的數的下標
$len = count($arr);
$half_len = floor($len/2);//向下取整，取整的值是循環的次數
for($i=0;$i<$half_len;$i++){
$j = $arr[$i];
//判斷數組個數奇偶
if($len%2!=0){ //奇數

$k = $half_len*2-$i;
}else{
//偶數
$k = $half_len*2-$i-1;
}
$arr[$i] = $arr[$k];
$arr[$k] = $j;
}
echo "<pre>";
print_r($arr);
echo "</pre>";

9.PHP數字金額轉換成大小格式 function daxie($num){
$da_num = array("零","一","二","三","四","五","六","七","八","九");
$str = ‘‘;
if(is_numeric($num) && strlen($num)>0){
for($i=0;$i<strlen($num);$i++){
$str .= $da_num[substr($num,$i,1)];
}
}
return $str;
}
echo daxie(1896);

PHP中關於數組的運算題