DSA_HT_New

class HashTable {
    constructor(size = 7) {
        this.dataMap = new Array(size);
    }

    _hash(key) {
        let hash = 0;
        for ( let i = 0; i < key.length; i++ ) {
            hash = ( hash + key.charCodeAt(i) * 23 ) % this.dataMap.length;
        }
        return hash;
    }

    set(key, value) {
        let index = this._hash(key);
        if ( !this.dataMap[index] ) {
            this.dataMap[index] = [];
        }
        this.dataMap[index].push([key, value]);
        return this;
    }

    get(key) {
        const index = this._hash(key);
        if ( index >= this.dataMap.length ) return undefined;
        if ( !this.dataMap[index] ) return undefined;
        for ( let i = 0; i < this.dataMap[index].length; i++ ) {
            if ( this.dataMap[index][i][0] === key ) return this.dataMap[index][i][1];
        }
        return undefined;
    }

    keySet() {
        let allKeys = [];
        this.dataMap.forEach(element => {
            if ( element.length > 0 ) {
                element.forEach(entry => {
                    allKeys.push(entry[0]);
                });
            }
        });
        return allKeys;
    }

}

function test() {
    let ht = new HashTable();
    ht.set('bolts', 1400);
    ht.set('washers', 50);
    ht.set('lumber', 10);
    ht.get('lumber');
    console.log(ht.keySet());
    console.log(ht);
}

test();