yangtaeho

const odd = n=> !!(n & 0x1);
const half = n=>n >> 1;
{
    // 내가 짠거
    const odd = n=>half(n) == half(n - 1);
    const half = n=>Math.floor(n/2);
}
{
    // hika pp. 29
    // n == parseInt(n/2) + parseInt(n/2); // 짝수인가? #1