js 内容相同的数据合并

const data = [
  { id: 1, name: 'Alice', age: 25 },
  { id: 1, name: 'Alice', city: 'New York' },
  { id: 2, name: 'Bob', age: 30 },
];

const mergedData = data.reduce((acc, current) => {
  const existing = acc.find(item => item.id === current.id);
  if (existing) {
    Object.assign(existing, current);
  } else {
    acc.push(current);
  }
  return acc;
}, []);

console.log(mergedData);

const data = [
  { id: 1, name: 'Alice' },
  { id: 2, name: 'Bob' },
  { id: 1, name: 'Alice' },
];

const uniqueData = Array.from(new Map(data.map(item => [item.id, item])).values());

console.log(uniqueData);

const sales = [
  { product: 'Apple', quantity: 10 },
  { product: 'Banana', quantity: 5 },
  { product: 'Apple', quantity: 20 },
];

const aggregatedSales = sales.reduce((acc, current) => {
  acc[current.product] = (acc[current.product] || 0) + current.quantity;
  return acc;
}, {});

console.log(aggregatedSales);