/* package whatever; // don't place package name! */

import java.util.*;
import java.util.stream.*;
import java.util.function.*;

/* Name of the class has to be "Main" only if the class is public. */
class Ideone
{
	public static void main (String[] args) throws java.lang.Exception
	{
    String bitStr = "100011101100111110011100";
    
	int maxLength = Arrays.stream(bitStr.split("0+"))
      .mapToInt(String::length)
      .reduce(0, Math::max);

    System.out.println( maxLength);
}
}