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import { memo, useState } from 'react';

function compare(oldProps, newProps) {
  return true;
}

const Greeting = memo(function Greeting({ name }) {
  console.log('Greeting was rendered at', new Date().toLocaleTimeString());
  return (
    <h3>
      Hello{name && ', '}
      {name}!
    </h3>
  );
}, compare);

export default function MyApp() {
  const [name, setName] = useState('');
  const [address, setAddress] = useState('');
  return (
    <>
      <label>
        Name{': '}
        <input value={name} onChange={(e) => setName(e.target.value)} />
      </label>
      <label>
        Address{': '}
        <input value={address} onChange={(e) => setAddress(e.target.value)} />
      </label>
      <Greeting name={name} />
    </>
  );
}