import java.io.BufferedReader;
import java.io.InputStreamReader;

public class Main {
    public static void main(String[] args) throws Exception {
        BufferedReader rd = new BufferedReader(new InputStreamReader(System.in));
        String weather = rd.readLine();
        String input = rd.readLine();

        int result = 0;
        for(int i=0; i<3; i++) {
            if(weather.charAt(i) == input.charAt(i)) {
                result++;
            }
        }
        System.out.print(result);
    }
}
/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