LeetCode/src/easy/BinaryNumberwithAlternatingBits.java at master · chenyiAlone/LeetCode · GitHub

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package easy;
/**
 * ClassName: BinaryNumberwithAlternatingBits.java
 * Author: chenyiAlone
 * Create Time: 2019/10/24 20:39
 * Description: No.693 Binary Number with Alternating Bits
 * 思路:
 *
 * Given a positive integer, check whether it has alternating bits: namely, if two adjacent bits will always have different values.
 *
 * Example 1:
 * Input: 5
 * Output: True
 * Explanation:
 * The binary representation of 5 is: 101
 * Example 2:
 * Input: 7
 * Output: False
 * Explanation:
 * The binary representation of 7 is: 111.
 * Example 3:
 * Input: 11
 * Output: False
 * Explanation:
 * The binary representation of 11 is: 1011.
 * Example 4:
 * Input: 10
 * Output: True
 * Explanation:
 * The binary representation of 10 is: 1010.
 *
 */
public class BinaryNumberwithAlternatingBits {

    public boolean hasAlternatingBits(int n) {
        int b = (n & 1) ^ 1;
        while (n > 0) {
            if ((n & 1) == b) return false;
            b ^= 1;
            n >>>= 1;
        }
        return true;
    }

}