Counter game

• Time : O(logn)
• Space : O(1)

string counterGame(long n) {
    bool louise = true;
    while(n != 1) {
        long lg = log2(n);
        if(1ll<<lg == n) n>>=1;
        else n -= 1ll<<lg;
        louise = !louise;
    }
    return !louise ? "Louise" : "Richard";
}