아래 값들의 typeof, Boolean, Number 결과를 예측하고 출력해보세요.
const a = ''; const b = '0'; const c = 0; const d = null;
const e = undefined;
const a = '';
const b = '0';
const c = 0;
const d = null;
const e = undefined;
console.log(typeof a, Boolean(a), Number(a));
console.log(typeof b, Boolean(b), Number(b));
console.log(typeof c, Boolean(c), Number(c));
console.log(typeof d, Boolean(d), Number(d));
console.log(typeof e, Boolean(e), Number(e));