import java.util.Scanner;
import java.util.stream.Stream;

public class Main {
    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        String str  = sc.nextLine();
        String[] astr = str.split(""); //状況に合わせて
        String str2  = sc.nextLine();
        String[] astr2 = str2.split(""); //状況に合わせて
        int flag = 0;
        sc.close();

        for(int i=0;i<astr.length;i++){
            if(astr[i].equals(astr2[i])){
                flag +=1;
            }
        }
        System.out.println(flag);
    }
}
/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