Strings in programming tutorial.

Strings in programming tutorial.

• 1.
  Today Our Topicis ‘’STRING”
• 2.
  Introduction  Strings arearray of characters i.e. they are characters arranged one after another in memory. Thus, a character array is called string.  Each character within the string is stored within one element of the array successively.  A string is always terminated by a null character (i.e. slash zero 0).
• 3.
  Arrays and Strings… Operations performed on character strings include:  Reading and writing strings  Copying one string to another  Combining strings together  Comparing strings for equality  Extracting a portion of a string
• 4.
   A stringvariable is declared as an array of characters.  Syntax: char string_name[size];  E.g. char name[20];  When the compiler assigns a character string to a character array, it automatically supplies a null character (‘0’) at the end of the string
• 5.
  Initializing String Variables Strings are initialized in either of the following two forms: char name[4]={‘R’,‘A’,‘M’, ‘0’}; char name[]={‘R’,‘A’,‘M’, ‘0’}; char name[4]=“RAM”; char name[]=“RAM”;  When we initialize a character array by listing its elements, the null terminator or the size of the array must be provided explicitly. R A M 0 name[0] name[1] name[2] name[3]
• 6.
  Reading and displayingStrings  It can be done manually.
• 7.
  Using printf() andscanf()
• 8.
  Using gets() andputs()
• 9.
  Passing String tofunction
• 10.
  String handling functions Strings need to be manipulated by programmer.  It can be done manually but is time consuming.
• 11.
  Counting length ofthe string #include <stdio.h> void main() { char input_string[50]; int i=0, length=0; clrscr(); printf("nEnter your text:t"); gets(input_string); while(input_string[i]!='0') { length++; i++; } printf("nThe length of your text is: %d character(s)", length); }
• 12.
   There arevarious string handling functions define in string.h some of them are:
• 13.
  void main() { char string[25]; clrscr(); printf("nInputstring to be reversed:"); gets(string); strrev(string); printf("nThe reversed string is: %s", string); getch(); } 13 Using Revers Function “Strrev()”
• 14.
  Arrays of Strings String is array of characters.  Thus an array of string is 2-D array of characters.  E.g. char names[5][10];  Here, names[5][10] means 5 names having 10 characters each. 1 4
• 15.
  void main() { char names[5][10]; inti; clrscr(); printf("nEnter name of 5 persons:"); for(i=0;i<5;i++) scanf("%s", names[i]); printf("nThe names are:"); for(i=0;i<5;i++) printf("n%s", names[i]); getch(); } 1 5