String Definition: What It Means In The World Of Computer Programming

If you are a budding programmer or if you are appearing for an interview, it is essential for you to brush up on your programming basics at regular intervals.

One such fundamental concept is String. A string in programming is a collection of characters, either as a variable or a literal constant.

The concept of string may seem easy, but performing operations on any String can be a bit tricky. Therefore, you should revise your basics frequently and practice various string operations like the subsequence of a string, a palindrome of a string, or the longest palindromic subsequence of a string.

In this post, we are going to talk about what Strings mean in programming and what all you need to know about it.

What Does String Mean In Programming

A string is an array of characters. It contains letters, symbols, and numbers. All these elements are stored in an array in a sequence.

In most programming languages, strings are denoted by a quotation mark. No matter what type of elements a string contains, it will always be stored in the form of text in the system.

For better understanding, consider the following example:

If you have initialized any variable with a value of 5, it will be considered an integer value by your system. However, in case you have initialized it as “5”, the system will automatically pick it up as a character. You can not use such value in any calculations.

Another thing that you need to know about strings is that they are stored in a sequence. So, if you have stored a string as “I love programming”, it will be stored in the same way. for instance, if you find a string with programming love, you will not find any results.

Strings are also used by many websites to store user credentials like passwords, usernames, and content on the website.

Characteristics Of A String

Here are some characteristics of string in programming that you need to know before writing a program on the same.

Sequence Of Characters

A string is simply a sequence of characters that include numbers, letters, and symbols. You can also define a string where there are only numbers or combinations of two or more types of characters.

Empty Strings

As the name suggests, an empty string is a string with no values. You can easily initialize a string by keeping the quotation marks empty.

Also, you must know that an empty string and space are different. Space itself is a character and occupies the length of one.

Length Of String

To count the length of a string, you can simply count the characters in the string. Although most programming languages have an in-built function to count the length of a string, you can still count the characters to know the length of a particular string.

String Case

A string can be written in different cases. For example, the whole string can be written in UPPERCASE, lowercase, Sentence case, and Capital Case.

Mutability Of A String

Mutability refers to the ability to change. An object is considered mutable when you can change it. In almost all programming languages, strings can be changed and hence are considered mutable.

Common Operations On A String

Now that we are talking about in detail what strings are, let’s take a look at all the operations that you can carry out on a string. Here are the common operations on a string.

Substring

A substring is a part of your original string. However, you need to know that there is an individual meaning to a substring.

If you wish to access a substring, you will need to have the following details:

String's name

Substring's length

Position of the initial element of the substring in the main string.

Indexing

Another operation that you can carry out on a string is indexing. It is defined as the process of finding the location of the initial presence of a string pattern. You may also call it pattern matching.

In case there is no such pattern found, the operation will give a 0 return value.

Concatenation

Concatenation on a string implies merging the two strings. Consider that you have two strings A and B. When you concatenate strings A and B, the resulting string will have the elements from string A first and then from string B.

Subsequence Of A String

The subsequence of a string can be defined as the sequence that you derive from the original string without modifying the order of the original string.

For better understanding, consider a string, “programming”. This string can have a subsequence “program” or “gram” but it can not have a subsequence “margin”. This is because in the subsequence “margin”, the sequence of the original string is not followed.

If you are working with subsequences, here are some operations that you can use on the subsequence of a string.

Print All Subsequence Of A String

In this, you can provide a string and then print all the subsequences of a string.

For example, if you have a string “ahbgdc” when you print all subsequences of a string, you can get the output: ahbgd, abc.

Longest Palindromic Subsequence

Another operation that you can apply to a subsequence is to find the longest Palindromic subsequence of the same.

It will display the length of the largest subsequence of a string which is also Palindromic. For example, if you have a string “Abbbc”, the length of the longest palindromic subsequence is 3.

Conclusion

The string is one of the fundamental and crucial concepts that you have to get hold of to work well in coding. Even if you are going for an interview with an IT company, concepts like the subsequence of a string, the longest Palindromic subsequence, and finding the length of the subsequence are often asked.

We have tried to provide you with a clear understanding of what strings are in a programming language and how you can use the same.