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