## Algorithm

Hacker rank Problem Name: 10 Days of JavaScript - Day 7: Regular Expressions II

# Day 7: Regular Expressions II

Complete the function in the editor below by returning a RegExp object, re, that matches any string s satisfying both of the following conditions:

• String s starts with the prefix Mr., Mrs., Ms., Dr., or Er.
• The remainder of string s (i.e., the rest of the string after the prefix) consists of one or more upper and/or lowercase English alphabetic letters (i.e., [a-z] and [A-Z]).

## Constraints

• The length of string s is >= 3.

## Output Format

The function must return a RegExp object that matches any string s satisfying both of the given conditions.

## Explanation 0

This string starts with Mr., followed by an English alphabetic letter (X).

## Explanation 1

This string starts with Mrs., followed by an English alphabetic letter (Y).

## Explanation 2

This string starts with Dr# instead of Dr., so it’s invalid.

## Explanation 3

This string starts with Er but there is a space before the period (.), making the string invalid.

## Code Examples

### #1 Code Example with Javascript Programming

```Code - Javascript Programming```

``````
'use strict';

process.stdin.resume();
process.stdin.setEncoding('utf-8');

let inputString = '';
let currentLine = 0;

process.stdin.on('data', inputStdin => {
inputString += inputStdin;
});

process.stdin.on('end', _ => {
inputString = inputString.trim().split('\n').map(string => {
return string.trim();
});

main();
});

return inputString[currentLine++];
}

function regexVar() {
/*
* Declare a RegExp object variable named 're'
* It must match a string that starts with 'Mr.', 'Mrs.', 'Ms.', 'Dr.', or 'Er.',
* followed by one or more letters.
*/
var re = (/^(Mr\.|Dr\.|Er\.|Ms\.|Mrs\.)\s?[a-z|A-Z]+\$/);

/*
* Do not remove the return statement
*/
return re;
}

``````
Copy The Code &

Input

cmd
Mr.X

Output

cmd
true