231. Power of Two | 判断2的幂

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

Credits:
Special thanks to @jianchao.li.fighter for adding this problem and creating all test cases.

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思路：位操作。

public class Solution {
    public boolean isPowerOfTwo(int n) {
	
		boolean isPower = false;

		int i = 0;
		int t;
		while (n > 0) {
			t = n & 0x1;
			if (t == 1) {
				i++;
				if (i > 1) {
					isPower = false;
					break;
				}
			}
			n = n >> 1;
			isPower = true;
		}
		return isPower;
	}
}