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<p>斐波那契數列：1，1，2，3，5，8，13，21，34，55，89，144........... </p>
<p>求斐波那契數列第ｎ項的值</p>
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<script type="text/javascript">
var n = prompt("請輸入數字n")
var num1 = 1;
var num2 = 1;
for(var i = 3; i <= n; i++) {
var temp = num2;
num2 = num1 + num2;
num1 = temp;
}
alert(num2);
</script>
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