Algorithm
Hacker rank Problem Name: 10 Days of JavaScript -
Hacker rank Problem Link: https://www.hackerrank.com/challenges/js10-regexp-2/problem?isFullScreen=true
Day 7: Regular Expressions II
Task
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.
Sample Input 0
| 1 | Mr.X | 
Sample Output 0
| 1 | true | 
Explanation 0
This string starts with Mr., followed by an English alphabetic letter (X).
Sample Input 1
| 1 | Mrs.Y | 
Sample Output 1
| 1 | true | 
Explanation 1
This string starts with Mrs., followed by an English alphabetic letter (Y).
Sample Input 2
| 1 | Dr#Joseph | 
Sample Output 2
| 1 | false | 
Explanation 2
This string starts with Dr# instead of Dr., so it’s invalid.
Sample Input 3
| 1 | Er .Abc | 
Sample Output 3
| 1 | false | 
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();    
});
function readLine() {
    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;
}
Input
Output
