import java.util.ArrayList;
import java.util.List;
import java.util.Scanner;

public class Main { 
    public static void main(String[] args) {
    	Scanner sc = new Scanner(System.in);
    	String predict = sc.nextLine();
    	String actual = sc.nextLine();

    	int result = 0;
    	for(int i = 0;i<predict.length();i++) {
    		char predictChar = predict.charAt(i);
    		if(predictChar == actual.charAt(i)) {
    			result++;
    		}
    	}

    	System.out.println(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