Java 15:

import java.io.*;
import java.util.*;
import java.util.regex.Pattern;
import java.util.regex.Matcher;
public class Solution {
    public static void main(String[] args) {
        Scanner scanner = new Scanner(System.in);
        Pattern pattern = Pattern.compile("^(Mr\\.|Mrs\\.|Ms\\.|Dr\\.|Er\\.)([a-z]|[A-Z])+$");
        Matcher matcher = pattern.matcher(scanner.nextLine());
        System.out.println(matcher.find());
    }
}

JavaScript:

var Regex_Pattern = /^(Mr|Mrs|Ms|Dr|Er){1}.[a-zA-Z]+$/;

pasess all test cases

Regex_Pattern = r'^(Mrs|Mr|Ms|Dr|Er)[\.][a-zA-Z]+$'

why this regex not worked for testcase 1 (Mr#DOSHI) is matched correctly how ?

**explain anyone **

r'^(Mr.|Mrs.|Dr.|Er.){1}[a-zA-Z]+$'

import re import webbrowser

def add(x, y): return x + y

def subtract(x, y): return x - y

def multiply(x, y): return x * y

def divide(x, y): if y != 0: return x / y else: return "Error: Division by zero"

def calculator(): print("Simple Calculator") print("Select operation:") print("1. Add") print("2. Subtract") print("3. Multiply") print("4. Divide")

choice = input("Enter choice (1/2/3/4): ")

if choice not in ['1', '2', '3', '4']:
    print("Invalid Input")
    return

num1 = float(input("Enter first number: "))
num2 = float(input("Enter second number: "))

if choice == '1':
    print(num1, "+", num2, "=", add(num1, num2))
elif choice == '2':
    print(num1, "-", num2, "=", subtract(num1, num2))
elif choice == '3':
    print(num1, "*", num2, "=", multiply(num1, num2))
elif choice == '4':
    result = divide(num1, num2)
    print(num1, "/", num2, "=", result)

# Including a hyperlink to https://carxapk.net/ in a comment
# Uncomment the next line if you want to open the link in a web browser
# webbrowser.open("https://carxapk.net/")

if name == "main": calculator()