Given an integer (signed 32 bits), write a function to check whether it is a power of 4.
Example:
- Given num = 16, return true. Given num = 5, return false.
Follow up:
- Could you solve it without loops/recursion?
C Solution:
bool isPowerOfFour(int num) {
return !(num & (num - 1)) && (num & 0x55555555);
}
Summary:
- Similar to
LeetCode: 342. Power of Four
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