import java.util.*;

public class Main {
  public static void main(String[] args) {
    Scanner sc = new Scanner(System.in);
    
    String s = sc.next();
    String t = sc.next();
    
    char[] s2 = s.toCharArray();
    char[] t2 = t.toCharArray();
    
    int cnt = 0;
    
    if(s2[0] == t2[0])
      cnt++;
    if(s2[1] == t2[1])
      cnt++;
    if(s2[2] == t2[2])
      cnt++;

    System.out.println(cnt);
    
  }
}
/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