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<html lang="en">
<head>
<meta charset="UTF-8">
<meta name="viewport" content="width=device-width, initial-scale=1.0">
<meta http-equiv="X-UA-Compatible" content="ie=edge">
<title>Document</title>
<script>
window.onload = function () {
var number1 = document.getElementById("number1");//獲取元素
var number2 = document.getElementById("number2");
function fn(a) {//定義函數 用遞歸
if (a <= 2) {//臨界值設置
return 1;
} else {
return fn(a - 1) + fn(a - 2);//調用自身
}
}
btn.onclick = function () {//點擊事件
var num1 = number1.value;//獲取元素
//console.log(num1);
var m = fn(num1);
//console.log(m);
number2.value = m;//寫入文本框
}
}
</script>
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<body>
請輸入數字：
<input type="text" id="number1">
<input type="button" value="生成" id="btn">
<br> 斐波那契數：
<input type="text" id="number2">
</body>
</html>