Power of Two

Desicription

Given an integer, write a function to determine if it is a power of two.

Example 1:

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Input: 1
Output: true
Explanation: 20 = 1

Example 2:

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Input: 16
Output: true
Explanation: 24 = 16

Example 3:

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Input: 218
Output: false

Solution

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class Solution {
public:
bool isPowerOfTwo(int n) {
if(n <= 0) {
return false;
} else {
return !(n&(n-1));
}
}
};