JSFiddle - React, Tailwind, and code Playground

JavaScript

$(document).ready(function(){
    var products = {};
    
    for(var i = 0; i < 300; i++){
        products["product" + (i + 1)] = {}
        products["product" + (i + 1)]["qtd" + (i + 1)] = i + 1
    }
    
    //Busca pela key
    console.log(products["product" + 400]); //undefined
    console.log(products["product" + 299]); //{qtd: 299}
    console.log(products["product" + 22]); //{qtd: 22}
    console.log(products["product" + 301]); //undefined
    //Assim fica até mais fácil fazer a busca:
    if(products.product400){
        if(products.product400.qtd400){
        console.log(products["product" + 400]["qtd400"]);//não acha
        }
    }
    if(products.product200){
        if(products.product200.qtd200){
        console.log(products["product" + 200]["qtd200"]);//200
        }
    }
    
    //Busca fazendo loop
    console.log(search("product" + 400))//null
    console.log(search("product" + 299)) //{qtd: 299}
    console.log(search("product" + 22)) //{qtd: 22}
    console.log(search("product" + 301)) //null
    
    function search(name){
        for (var k in products) {
            if (k == name) {       
                return products[k];
            }
        }
        return null;
    }
});