import java.util.*;
public class Main{
  public static void main(String[] args) {
    Scanner sc = new Scanner(System.in);
    String s = sc.nextLine();
    String t = sc.nextLine();
    int n = 0;

    if(s.substring(0,1).equals(t.substring(0,1))){
      n++;
    }
    if(s.substring(1,2).equals(t.substring(1,2))){
      n++;
    }
    if(s.substring(2,3).equals(t.substring(2,3))){
      n++;
    }
    System.out.println(n);
  }
}

/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