import java.util.*;
 
public class Main{
	public static void main(String[] args){
		Scanner sc = new Scanner(System.in);
		String s = sc.nextLine();
		String c = sc.next();
		char[] sChar = new char[3];
		char[] cChar = new char[3];
		int count = 0;
		for(int i = 0; i < 3; i++){
			sChar[i] = s.charAt(i);
			cChar[i] = c.charAt(i);
			if(sChar[i] == cChar[i]){
				count++;
			}
		}
		System.out.println(count);
	}
 
}
/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