ex15-10-1

ソース

const d1 = new Date(1996, 2, 1);
const d2 = new Date(2009, 4, 27);
const msDiff = d2 - d1;
console.log(msDiff); // 417744000000   （ミリ秒）
const daysDiff = msDiff/1000/60/60/24;
console.log(daysDiff); // 4835   （日）