import java.util.*;
class Main
{
	public static void main(String args[])
	{
		Scanner sc=new Scanner(System.in);
		String s=sc.next();
		String t=sc.next();
		
		String s1=s.substring(0,1);
		String s2=s.substring(1,2);
		String s3=s.substring(2,3);
		
		String t1=t.substring(0,1);
		String t2=t.substring(1,2);
		String t3=t.substring(2,3);
		
		int result=0;
		
		if(s1.equals(t1)){
			result+=1;
			}
		else{
			result+=0;
		}
		if(s2.equals(t2)){
			result+=1;
		}
		else{
			result+=0;
		}
		if(s3.equals(t3)){
			result+=1;
		}
		else{
			result+=0;
		}
		System.out.println(result);
	}
}
/tmp/hf-datasets-cache/medium/datasets/42704881117311-config-parquet-and-info-qiankunmu-Project_CodeNet-896c9d36/hub/datasets--qiankunmu--Project_CodeNet_Python800_and_Java250/snapshots/c899fde44a77ba1cc14973ed3de064e4ff3aadc7/Project_CodeNet_Java250.tar.gz