Character counting in Javascript

character-count.js

// FIRST METHOD
// Count using array
arr = new Array(26).fill(0);
s = "ABCAZZ" // Input String

for (var i = 0; i < s.length; i++) {
    var index = s.charCodeAt(i) - 'A'.charCodeAt(0);
    arr[index] += 1;
}

console.log(arr) // Output


// SECOND METHOD
// Count using object or hashmap
arr = {};
s = "ABCAZZ" // Input String

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

    if (arr[s.charAt(i)])
        arr[s.charAt(i)] += 1
    else 
        arr[s.charAt(i)] = 1;
}

console.log(arr) // Output