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();
    
    String oneS = S.substring(0,1);
    String twoS = S.substring(1,2);
    String threeS = S.substring(2,3);
    
    String oneT = T.substring(0,1);
    String twoT = T.substring(1,2);
    String threeT = T.substring(2,3);
    
    int count = 0;
    if (oneS.equals(oneT)) {
      count ++;
    }
    if (twoS.equals(twoT)) {
      count ++;
    }
    if (threeS.equals(threeT)) {
      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