Repeated String Match

Problem statement

Given two strings a and b, return the minimum number of times you should repeat string a so that string b is a substring of it. If it is impossible for b​​​​​​ to be a substring of a after repeating it, return -1.

Notice: string "abc" repeated 0 times is "", repeated 1 time is "abc" and repeated 2 times is "abcabc".

Example 1:

Input: a = "abcd", b = "cdabcdab"Output: 3Explanation: We return 3 because by repeating a three times "abcdabcdabcd", b is a substring of it.

Example 2:

Input: a = "a", b = "aa"Output: 2

Constraints:

• 1 <= a.length, b.length <= 104
• a and b consist of lowercase English letters.

My solution

/**
 * @param {string} a
 * @param {string} b
 * @return {number}
 */
var repeatedStringMatch = function(a, b) {
    const reminder = Math.ceil(b.length / a.length)  
    
    if (a.repeat(reminder).includes(b)) {
        return reminder;
    }
    
    // console.log(a.repeat(reminder + 1))
    if (a.repeat(reminder + 1).includes(b)) {
        return reminder + 1;
    }
    
    return -1
};