1780. Check if Number is a Sum of Powers of Three

Given an integer n, return true if it is possible to represent n as the sum of distinct powers of three. Otherwise, return false.

An integer y is a power of three if there exists an integer x such that y == 3x.

class Solution {
public:
    bool checkPowersOfThree(int n) {
        int lg3 = log(n) / log(3);
        while(n) {
            int p = pow(3,lg3);
            if(n >= p) {
                n -= p;
                if(n >= p) return false;
            }
            lg3--;
        }
        return true;
    }
};