<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<meta http-equiv="X-UA-Compatible" content="IE=edge">
<meta name="viewport" content="width=device-width, initial-scale=1.0">
<title>Document</title>
</head>
<body>
<script>
//1,1,2,3,5,8,13 //输出的结果
//1,2,3,4,5,6,7 //输入的数字
/*
7 = fn(6) + fn(5) ~ 8 + 5 =13
6 = fn(5) + fn(4) ~ 5 + 3 =8
5 = fn(4) + fn(3) ~ 3 + 2 =5
4 = fn(3) + fn(2) ~ 2 + 1 =3
3 = fn(2) + fn(1) ~ 1 + 1 =2
2 = fn(1) + fn 直接回退
*/
function fb(n){
if(n === 1 || n === 2){
return 1;
}
return fb(n-1)+fb(n-2)
}
console.log(fb(5));
</script>
</body>
</html>
