function solve(input) { const carBrands = new Map(); input.forEach((el)=> { let [brand, model, count] = el.split(" | "); count = Number(count); if (carBrands.has(brand)) { let carBrand = carBrands.get(brand); if (carBrand.has(model)) { let carModel = carBrand.get(model); carModel += count; carBrand.set(model, carModel); } else { carBrand.set(model, count); } } else { const modelMap = new Map(); modelMap.set(model, count); carBrands.set(brand, modelMap); } }) for (const key of carBrands.keys()) { console.log(key); const brand = carBrands.get(key); for (const [model, count] of brand) { console.log(`###${model} -> ${count}`); } } }