import java.io.BufferedReader;
import java.io.*;
import java.util.*;
import java.util.ArrayList;
import java.util.Iterator;
import java.util.List;
import java.util.Collections;

public class Main {
	public static void main(final String[] args){
    
        Scanner sc = new Scanner(System.in);

        String s = sc.next();
        String t = sc.next();
        char[] work = new char[s.length()];
        char[] work2 = new char[t.length()];
        int count = 0;

        for(int i = 0; i < s.length(); i++){
                work[i] = s.charAt(i);
            }

        for(int i = 0; i < t.length(); i++){
                work2[i] = t.charAt(i);
        }

        for(int i = 0; i < 3; i++){
            if(work[i] == work2[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