import java.util.*;
class Main
{
  public static void main(String[] args)
  {
    Scanner sc = new Scanner(System.in);
    
    String a = sc.next();
    String b = sc.next();
    
    String a1 = a.substring(0,1);
    String a2 = a.substring(1,2);
    String a3 = a.substring(2,3);
    
    String b1 = b.substring(0,1);
    String b2 = b.substring(1,2);
    String b3 = b.substring(2,3);
    
    int count = 0;
    
    if(a1.equals(b1)){
      count++;
    }
    if(a2.equals(b2)){
      count++;
    }
    if(a3.equals(b3)){
      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