Return whether or not there are two numbers in the list that add up to k.

twoSum.ts

const twoSum = (numbers:number[], k: number): Boolean => {

    const rec:Record<number,number>= {};

    for(const n of numbers){
        rec[n] = n;
        if(rec.hasOwnProperty(k-n)) return true;
    }
 
    return false;
}