import java.util.Scanner;

public class Main {
	public static void main(String args[]) {	
		Scanner sc = new Scanner(System.in);
		String s = sc.next();
		String a = sc.next();
		
		int c = 0;
		if(s.charAt(0)==a.charAt(0))c++;
		if(s.charAt(1)==a.charAt(1))c++;
		if(s.charAt(2)==a.charAt(2))c++;
		
		System.out.println(c);
	}
}

/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