import java.util.*;
class Main {
public static void main(String[] args) {
Scanner sc = new Scanner(System.in);
  String str = sc.next();
  String str1 = sc.next();
  int cnt = 0;
  for(int i = 0; i<str.length(); i++) {
  char c = str.charAt(i);
    char c1 = str1.charAt(i);
    if(c==c1) 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