ee1e8abd87
* feat(tools): add seed/solution restore script * chore(curriculum): remove empty sections' markers * chore(curriculum): add seed + solution to Chinese * chore: remove old formatter * fix: update getChallenges parse translated challenges separately, without reference to the source * chore(curriculum): add dashedName to English * chore(curriculum): add dashedName to Chinese * refactor: remove unused challenge property 'name' * fix: relax dashedName requirement * fix: stray tag Remove stray `pre` tag from challenge file. Signed-off-by: nhcarrigan <nhcarrigan@gmail.com> Co-authored-by: nhcarrigan <nhcarrigan@gmail.com>
1.6 KiB
1.6 KiB
id, title, challengeType, videoUrl, dashedName
| id | title | challengeType | videoUrl | dashedName |
|---|---|---|---|---|
| 5900f3851000cf542c50fe98 | 问题25：1000位斐波纳契数 | 5 | problem-25-1000-digit-fibonacci-number |
--description--
Fibonacci序列由递归关系定义：
F
n
= F
n-1
- F
n-2
，其中F
1
= 1且F
2
= 1。
因此，前12个学期将是：
F
1
= 1
F
2
= 1
F
3
= 2
F
4
= 3
F
5
= 5
F
6
= 8
F
7
= 13
F
8
= 21
F
9
= 34
F
10
= 55
F
11
= 89
F
12
= 144
第12个学期F
12
是第一个包含三位数的术语。 Fibonacci序列中包含n个数字的第一项的索引是多少？
--hints--
digitFibonacci(5)应该返回21。
assert.strictEqual(digitFibonacci(5), 21);
digitFibonacci(10)应该返回45。
assert.strictEqual(digitFibonacci(10), 45);
digitFibonacci(15)应该返回69。
assert.strictEqual(digitFibonacci(15), 69);
digitFibonacci(20)应该返回93。
assert.strictEqual(digitFibonacci(20), 93);
--seed--
--seed-contents--
function digitFibonacci(n) {
return n;
}
digitFibonacci(20);
--solutions--
const digitFibonacci = (n) => {
const digits = (num) => {
return num.toString().length;
};
let f1 = 1;
let f2 = 1;
let index = 3;
while (true) {
let fn = f1 + f2;
if (digits(fn) === n) return index;
[f1, f2] = [f2, fn];
index++;
}
};