DSA/C++/LeetCode/0231.cpp at main · spycedcoffee/DSA · GitHub

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//Solution 1 :-
//Recursive
class Solution {
public:
    bool isPowerOfTwo(int n) {
        if(n <= 0)
            return false;

        else if(n == 1)
            return true;

        else if(n % 2 != 0)
            return false;

        else{
            while(n > 2){
                if(n % 2 != 0)
                    return false;

                n /= 2;
            }

            return true;
        }
    }
};


//Solution 2 :-
//Bit manipulation
class Solution {
public:
    bool isPowerOfTwo(int n) {
        if(n <= 0)
            return false;

        bool ans = n & (n - 1);

        if(!ans)
            return true;

        else
            return false;
    }
};