Complement of binary

class Solution {
    public int bitwiseComplement(int N) {
        if(N==0) return 1;
        String binary="";
        int result=0;
        while(N>0){
            int b=N%2;
            binary=b+""+binary;
            System.out.println(binary);
            N/=2;
        }
        
        for(int i=0; i<binary.length(); i++){
            if(binary.charAt(i)=='0'){
               result+=Math.pow(2,binary.length()-i-1); 
            }
        }
        return result;
    }
}
#Status:Solved