Javascript_DS/HashTables.html at main · Thellexcodes/Javascript_DS · GitHub

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<!DOCTYPE html>
<html lang="en">

<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
</head>

<body>
    <script>

        class HashTable {
            constructor(size = 50) {
                this.size = size;
                this.buckets = Array(this.size).fill(null).map(() => []);
            }


            _hash(key) {
                let hash = 0;
                for (let i = 0; i < key.length; i++) {
                    hash = (hash + key.charCodeAt(i) * i) % this.size;
                }
                return hash;
            }


            set(key, value) {
                const index = this._hash(key);
                const bucket = this.buckets[index];


                for (let i = 0; i < bucket.length; i++) {
                    const [bucketKey] = bucket[i];
                    if (bucketKey === key) {
                        bucket[i][1] = value;
                        return;
                    }
                }


                bucket.push([key, value]);
            }


            get(key) {
                const index = this._hash(key);
                const bucket = this.buckets[index];


                for (let i = 0; i < bucket.length; i++) {
                    const [bucketKey, bucketValue] = bucket[i];
                    if (bucketKey === key) {
                        return bucketValue;
                    }
                }


                return undefined;
            }


            remove(key) {
                const index = this._hash(key);
                const bucket = this.buckets[index];


                for (let i = 0; i < bucket.length; i++) {
                    const [bucketKey] = bucket[i];
                    if (bucketKey === key) {
                        bucket.splice(i, 1);
                        return true;
                    }
                }


                return false;
            }


            display() {
                return this.buckets.filter(bucket => bucket.length > 0);
            }
        }


        const hashTable = new HashTable();
        hashTable.set('name', 'Faisal');
        hashTable.set('age', 30);
        hashTable.set('city', 'Lagos');

        console.log(hashTable.get('name'));
        console.log(hashTable.get('age'));
        console.log(hashTable.get('city'));

        hashTable.remove('age')
        console.log(hashTable.get('age'))

        console.log(hashTable.display());
    </script>
</body>

</html>