Category Archives: Algorithm-Regex

Utopian Identification Number: Hackerrank

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Problem Statement:
A new identification number is given for every Citizen of the Country Utopia and it has the following format.

1. The string must begin with between 0 and 3 (inclusive) lowercase letters.
2. Immediately following the letters, there must be a sequence of digits. The length of this segment must be between 2 and 8, both inclusive.
3. Immediately following the numbers, there must be at least 3 uppercase letters.

Your task is to find out if a given identification number is valid or not.
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Detect HTML Tags: Hackerrank

Problem link:

Problem Statement:
In this problem you will use regular expressions to help you detect the various Tags used in an HTML document.

Here are a few examples of tags:

The “p” tag for paragraphs:

<p>This is a paragraph</p>

It is also okay to have one or more spaces before or after the tag name:

<  p >This is also a paragraph</p>

Then, there is also something called a void or an empty tag such as:


Some tags can also have attributes. For example, here we see the “a” tag which is used for adding links to a document.

<a href="">Google</a> 

There are also tags such as this which haven’t been split into an opening and closing tag:

In the above case, “a” is the tag and “href” is an attribute, the value of which is “”. Ignore any attributes. Your task is to find out all the tags present in the given document.
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