javascript - JS : Repeated string (Hackerrank Challenge)

Question

我正在做 Hackerrank 中的一项挑战，如下所示:

Lilah has a string, s, of lowercase English letters that she repeated infinitely many times.

Given an integer, n, find and print the number of letter a’s in the first n letters of Lilah’s infinite string. The first line contains a single string, s. The second line contains an integer, n.

我需要打印一个整数，表示通过无限次重复 S 创建的无限字符串的前 N ​​个字母中字母 a 的数量。

例如:

s is 'aba', n = 10.. The first n = 10 letters of the infinite string are 'abaabaabaa...' Because there are 7 a’s, we'll get 7 as the final answer

这是我的答案。它通过了前两个案例，但未通过其余案例。

function repeatedString(s, n) {
    var repeat = Math.round(n / s.length);
    var remainder = n % s.length;
    var answer = 0;
    for (var i = 0; i < s.length; i++) {
        if (s.charAt(i) == 'a') {
            answer += repeat;
            if (i < remainder)
                answer++;
        }
    }
    return answer;
}

如果有人可以看看这个并提出更好的解决方案，那就太好了。

Answer 1

//From a website i found it.

 const as = s.split("").filter(c => c === "a").length;
        const times = parseInt(n / s.length);
        const rest = n % s.length;

        const totalAs = times * as
            + s.slice(0, rest).split("").filter(c => c === "a").length

        return totalAs;