Given two strings s and t, return true if t is an anagram of s, and false otherwise.

Example 1:

Input: s = "anagram", t = "nagaram" Output: true

Example 2:

Input: s = "rat", t = "car" Output: false

Constraints:

1 <= s.length, t.length <= 5 * 104

To determine if one string is an anagram of another in JavaScript, you can follow these steps:

1. Check if the lengths of both strings are equal. If not, they can't be anagrams.
2. Count the frequency of each character in the first string.
3. Decrease the frequency of each character encountered in the second string.
4. If at any point the frequency becomes negative or after processing the second string, any character's frequency is not zero, the strings are not anagrams.

Here's a JavaScript function that implements this logic:

function isAnagram(s, t) {

    if (s.length !== t.length) {

        return false;

    }

    const count = {};

    // Count the frequency of each character in s

    for (let i = 0; i < s.length; i++) {

        const char = s[i];

        count[char] = (count[char] || 0) + 1;

    }

    // Decrease the frequency for each character in t

    for (let i = 0; i < t.length; i++) {

        const char = t[i];

        if (!count[char]) {

            return false; // char not found or frequency is 0, not an anagram

        }

        count[char]--;

    }

    return true;

}

// Test the function

console.log(isAnagram("anagram", "nagaram")); // Output: true

console.log(isAnagram("rat", "car")); // Output: false

This function first ensures the strings are of equal length. Then, it uses a `count` object to track the number of occurrences of each character in the first string and decreases the corresponding count for each character in the second string. If a character in the second string doesn't exist in the `count` object or its count drops below zero, the function returns false, indicating the strings are not anagrams. If all characters match appropriately, it returns true.