useMemo-calculation.ts

const computeExpensiveValue = (end: number) => {
  let result = 0;

  for (let i = 0; i < end * 1000000; i++) {
    for (let j = 0; i < end * 1000; j++) {
       result = result + i - j;
    }
  }

  return result;
};

const MyComponent = ({ end = 0 }) => {
  const memoizedNumber = React.useMemo<number>(computeExpensiveValue(end))
    
  return (
    <DisplayResult result={memoizedNumber} />
  );
}