java - calculating consecutive 1's in a Binary number

Question

import java.util.Scanner;
import java.util.Arrays;
class Solve
{
  public static void main(String args[])
  {
    Scanner in = new Scanner(System.in);
    int i=0,count=0;
    int[] arr = new int[10];
    int n =in.nextInt();
    while(n!=0)
    {
      arr[i]=n%2;
      i++;
      n=n/2;
    }
    System.out.println(Arrays.toString(arr));
  }

  }
}

I just want to calculate number of consecutive 1's. ? like 1110011001 will give me answer 5.. How can i do that??

Answer 1

System.out.println(Integer.toBinaryString(n).replaceAll("(0|(?<!1)1(?!1))", "").length());

The regex means: replace all 0's and any 1 not preceded or followed by another 1