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Standard streams in C language

A stream is nothing but a collection or sequence of bytes that is moved from main memory and I/O devices. The standard streams in ‘C’ are predefined streams. They are automatically opened whenever the program is executed. When the “main()” function of a C program is invoked, it already has predefined streams open and available for use. Two of these streams represent the standard input and output channels that will be opened for the transfer of data in the form of bytes. These streams are declared in the header file ‘stdio.h’. in total there are FIVE standard streams available, which are:

stdin : the standard input stream, which is the normal source of input for the program. The stream of data is transferred from standard input device like ‘keyboard’ to main memory referred in the form of variables.

stdout :  the standard output stream, which is used for normal output from the program. The stream of data is transferred from main memory referred in the form of variables to the output device like ‘monitor’.

stderr:  the standard error stream, which is used to output error messages and diagnostics from the program.

stdaux : the standard auxiliary device stream, which is used for the connected secondary devices.

stdprn : the standard printer stream, which is used for printing the data in the form hard copy from the program. The data is printed on die attached printer.

In the GNU system the shell provides the pipe and redirection facilities. With the help of these facilities the streams using the files and processes are specified. Most of the other operating systems also provide the similar mechanisms, but the details of usage may vary.

In the GNU C library, ' stdin', ‘stdout', and ' stderr' are normal variables which you can set just like others. For example, to redirect the standard output to a file, you could do:

fclose (stdout);

stdout = fopen (“output_file”, “w”);

Note however that in other systems ' stdin', ‘stdout', and ' stderr' are macros and cannot be assigned to any file in the normal way. But the function ' freopen ()' can be used to get the of closing one file and reopening another file.


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Binary Search Linear Search Works only on sorted items. such as  1,2,3,4,5,6  etc
Works on sorted as well as unsorted items. 12,4,5,3,2,1 etc Very efficient if the items are sorted Very efficient if the items are less and present in the beginning of the list. such as Suppose your list items are : 12,3,4,5,1 and you want to search 12 number then you get beginning in the list. Works well with arrays and not on linked lists. Works with arrays and linked lists.
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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 …