/*天気*/
import java.util.Scanner;

public class Main{
	public static void main(String[] args) {

		int i;
		int count = 0;

		Scanner sc = new Scanner(System.in);

		String S = sc.nextLine();
		String T = sc.nextLine();

		String[] SArray = S.split("");
		String[] TArray = T.split("");


		for(i = 0; i < 3;i++) {
			if(SArray[i].equals(TArray[i])) 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