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What is Variable Length String Format in C Language

As the name implies, variable–length strings don’t have a pre-defined length. In this string, neither the precise length nor maximum length is known at the time of creating it. The array storage structure for a string can expand or shrink to accommodate any number of characters. But, there should be a mechanism to indicate the end of the string. The two common techniques to implement variable length strings are described in the article.

Length Controlled String

A length controlled string is a string whose length is stored as part of the string itself. This technique uses a count that specifies string length. The count is normally stored as the first byte followed by the string. This count is used by the string manipulation functions to determine the actual length of the string data.
For example, the strings "DOT" and "PROGRAM" are stored using length controlled format are:

What is Varaible Length String Format in Computer Programming: C Language

Note: The first byte contains string length. Since its length is 1 byte (* bits) w can have a string length whose range is from 0 to 255. So, the string length should not exceed 255 characters.

The disadvantages can be overcome using delimited string. As we use various delimiters such as semicolons, colon, comma, period (.), in a sentence in English, the string can also be ended with delimiters.

Delimited String

In a variable length string, the string ends with a delimiter NULL (denoted by '0') character. This string which ends with a delimiter denoting the end of the string is called delimited string.

For example, the string "DOT" and "PROGRAM" are stored using a delimiter as shown here.

What is Varaible Length String Format in Computer Programming: C Language


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Binary Search Linear Search Works only on sorted items. such as  1,2,3,4,5,6  etc
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Memory representation of Linked List Data Structures in C Language

Memory representation of Linked List

             In memory the linked list is stored in scattered cells (locations).The memory for each node is allocated dynamically means as and when required. So the Linked List can increase as per the user wish and the size is not fixed, it can vary.

               Suppose first node of linked list is allocated with an address 1008. Its graphical representation looks like the figure shown below:

      Suppose next node is allocated at an address 506, so the list becomes,

  Suppose next node is allocated with an address with an address 10,s the list become,

The other way to represent the linked list is as shown below:

 In the above representation the data stored in the linked list is “INDIA”, the information part of each node contains one character. The external pointer root points to first node’s address 1005. The link part of the node containing information I contains 1007, the address of next node. The last node …