import java.util.*;

public class Main {
  public static void main(String[] args) {
    @SuppressWarnings("resource")
    Scanner sc = new Scanner(System.in);
    char[] expected = sc.next().toCharArray();
    char[] actual = sc.next().toCharArray();
    int cnt = 0;
    
    for (int i = 0; i < 3; i++) {
      cnt = (expected[i] == actual[i]) ? cnt + 1 : 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