import java.util.Scanner;

public class Main {

	public static void main(String[] args) {

		Scanner scanner = new Scanner(System.in);
		char[] yohouA   = new char[3];
		char[] zissaiA  = new char[3];

		String yohou  = scanner.nextLine();
		String zissai = scanner.nextLine();

		int count = 0;

		scanner.close();

		tenki(yohou,  yohouA);
		tenki(zissai, zissaiA);

		for(int i=0; i<3; i++) {

			if(yohouA[i] == zissaiA[i]){

				count++;

			}else {

				continue;

			}

		}

		System.out.println(count);

	}

	public static void tenki(String tenki, char[] array) {

		for(int i=0; i<3; i++) {

			array[i] = tenki.charAt(i);

		}

	}


}
/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