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面試前的筆試-實作題-費氏數列

費氏數列,是F1 = F2 = 1, Fn = Fn-1+Fn-2,給以下兩個範例,請實做出程式。
func(1) = 1
func(3) = 1 2 3 5 8

<?php
echo func(1);
echo func(3);

function f($x){
    if($x == 1 || $x == 2)  return 1;
    return f($x-1)+f($x-2);
}

function func($x){
    $ans = '';
    $len = $x*2-1;
    for($i = 1 ; $i<=$len ; $i++)
        $ans .= f($i+1) . ' ';
    return  $ans;
}
?>

今天應該是太緊張了...,看到這題我無法理解為什麼func(3) = 1 2 3 5 8,但回到房間在想起這件事情,原來是要我推理出可能的func,就馬上寫出來了。

好吧,看來今天的面試結果應該是無望了XD

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