读懂题意就出来了

class Solution {    public int binaryGap(int N) {        String s = Integer.toBinaryString(N);        int ans = 0;        int k = -1;        int i = 0;        while (s.charAt(i) == '0') i++;        for (; i < s.length(); i++) {            if (s.charAt(i) == '1') {                k++;                ans = Math.max(ans, k);                k = 0;            } else {                k++;            }        }        return ans;    }}