868. Binary Gap

Input: 22
Output: 2
Explanation: 
22 in binary is 0b10110.
In the binary representation of 22, there are three ones, and two consecutive pairs of 1's.
The first consecutive pair of 1's have distance 2.
The second consecutive pair of 1's have distance 1.
The answer is the largest of these two distances, which is 2.

Input: 5
Output: 2
Explanation: 
5 in binary is 0b101.

Input: 6
Output: 1
Explanation: 
6 in binary is 0b110.

Input: 8
Output: 0
Explanation: 
8 in binary is 0b1000.
There aren't any consecutive pairs of 1's in the binary representation of 8, so we return 0.

func binaryGap(N int) int {
    max,pre,next := 0,0,1
    for  ;N & 1 == 0 && N > 0; pre,N = pre+1, N >> 1{
    }
    
    for next,N = pre + 1,N>>1;N > 0; N>>=1 {
        for N & 1 == 0{
            next++
            N >>=1
        }
        if next -pre > max {
            max = next - pre
        }
        pre = next
        next += 1
    }
    
    return max
}

public int binaryGap(int N) {
        int res = 0;
        for (int d = -32; N > 0; N /= 2, d++)
            if (N % 2 == 1) {
                res = Math.max(res, d);
                d = 0;
            }
        return res;
    }