comparing and adding items to array of objects

Question

The below code is supposed to:

1) go through the two arrays,

2) if an item exist in both arrays, add its value to the value of the similar item in the first arra

Answer 1

You could use a hash table for the inventory and check against and update currInv.

var curInv = [[21, "Bowling Ball"], [2, "Dirty Sock"], [2, "cat"], ],
    newInv = [[21, "Bowling Ball"], [2, "Dirty Sock"], [3, "rags"], [3, "mugs"]],
    inventory = Object.create(null);

curInv.forEach(function (a) {
    this[a[1]] = a;
}, inventory);

newInv.forEach(function (a) {
    if (!this[a[1]]) {
        this[a[1]] = [0, a[1]];
        curInv.push(this[a[1]]);
    }
    this[a[1]][0] += a[0];
}, inventory);

console.log(curInv);

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