adventofcalendarday1_b.js

// complement sum
// ask "what is the complement for x number" and then "Do I have it?"
let goal = 2020
let marbles = new Set([1721, 979, 366, 299, 675, 1456])
let complement

main:
for(var marble of marbles){
    complement = goal - marble
    if(marbles.has(complement)){
        console.log(`${marble} + ${complement} = ${goal}`)
        // 299 + 1721 = 2020
        console.log(`${marble} * ${complement} = ${marble * complement}`)
        // 299 * 1721 = 514579
        break main
    }
}