[LeetCode] Problem 693 - Binary Number with Alternating Bits

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Given a positive integer, check whether it has alternating bits: namely, if two adjacent bits will always have different values.

Example

No.1

Input: 5

Output: True

Explanation:
The binary representation of 5 is: 101

No.2

Input: 7

Output: False

Explanation:
The binary representation of 7 is: 111.

No.3

Input: 11

Output: False

Explanation:
The binary representation of 11 is: 1011.

No.4

Input: 10

Output: True

Explanation:
The binary representation of 10 is: 1010.

Code

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public boolean hasAlternatingBits(int n) {
    int bit = n & 1;

    while ((n >>= 1) > 0) {
        if ((n & 1) == bit)
            return false;

        bit = n & 1;
    }

    return true;
}