KEMBAR78
String (Computer programming and utilization) | PPTX
 A string is a sequence of character that is treated
as a single data item.
 String is represented as a CHARACTER ARRAY.
Declaration of string
 Syntax:- char string_name[length];
 Example:- char name[5];
 This example declares an array name
which can store at the most 5
characters.
 Character array can be initialiized in two ways- as
individual character or as single string.
 Example:-
Char greet[10]= {‘h’, ’e, ’l’, ‘l’, ‘o’, ‘!’};
Char greet[10]=“hello!”;
Char greet[]=“hello!”;
 The compiler automatically stores the null
character at the end of the string. Memory
representation of char greet[]=“hello!”; is as
follows:
h e l l o ! 0
 We are familiar with two standard function for
reading input and writing output – scanf() and
printf() respectively.
 These functions with format specifiers %c and
%s can be used for input and output of
characters and strings.
 The example given in the next slide.
 Ex:- char color {6};
 Scanf(“%c”, & color); // reading char
 Scanf(“%s”, & color); // reading string
 printf(“%c”, & color); // writing char
 printf(“%s”, & color); // writing string
 WE have seen other I/o functions for
character and string –
getchar,putchar,gets,puts in the chapter 2.
 Strlen(s1):- Return the length of the string s1
excluding the null character.
 Strlwr(s1):- Convert the string s1 to lower
case.
 Strcat(s1,s2):- Appends a copy of string s2 to
end of s1 and terminates s1 with a null and a
return s1.
 Strcmp(s1,s2):- Compress s1 and s2 and
returns –ve if s1<s2 , +ve if s1>s2 , 0 if
s1=s2.
 Strcpy(s1,s2):- copies the string s2 into
s1,modifying the string s1.
 Strcmpi(s1,s2):- Compress s1 and s2
ignoring the case and return similar result as
strcmp.
 Strncmp(s1,s2,n):- compress the first n
character of string s1 and s2 and return
similar result as strcmp.
 Strupr(s1):- Convert the string s1 to
uppercase.
 Strchr(s1,c):- Returns a pointer to the first
occurrence of the character c in string s1.
 Strrchr(s1,c):- Returns a pointer to the last
occurrence of the character c in string s1.
 Strstr(s1,s2):- Returns a pointer to the first
occurrence of the string s2 in string s1.
 Strrev(s1):- Returns the reverse string of
string s1.
 Strtok(s1,s2):- Searches s1 for tokens that
are separated by delimiters specified in s2.
Returns the pointer to first char to first token
in s1.
 Steset(s1,c):- Sets all characters in string s1
to character c and quites when null character
is detected.
 Strnset(s1,c,n):- Sets the first char in string
s1 to char c and quits when nill char is
detected.
 Sscanf:- Divided lines into tokens.
String (Computer programming and utilization)

String (Computer programming and utilization)

  • 2.
     A stringis a sequence of character that is treated as a single data item.  String is represented as a CHARACTER ARRAY. Declaration of string  Syntax:- char string_name[length];  Example:- char name[5];  This example declares an array name which can store at the most 5 characters.
  • 3.
     Character arraycan be initialiized in two ways- as individual character or as single string.  Example:- Char greet[10]= {‘h’, ’e, ’l’, ‘l’, ‘o’, ‘!’}; Char greet[10]=“hello!”; Char greet[]=“hello!”;  The compiler automatically stores the null character at the end of the string. Memory representation of char greet[]=“hello!”; is as follows: h e l l o ! 0
  • 4.
     We arefamiliar with two standard function for reading input and writing output – scanf() and printf() respectively.  These functions with format specifiers %c and %s can be used for input and output of characters and strings.  The example given in the next slide.
  • 5.
     Ex:- charcolor {6};  Scanf(“%c”, & color); // reading char  Scanf(“%s”, & color); // reading string  printf(“%c”, & color); // writing char  printf(“%s”, & color); // writing string  WE have seen other I/o functions for character and string – getchar,putchar,gets,puts in the chapter 2.
  • 6.
     Strlen(s1):- Returnthe length of the string s1 excluding the null character.  Strlwr(s1):- Convert the string s1 to lower case.  Strcat(s1,s2):- Appends a copy of string s2 to end of s1 and terminates s1 with a null and a return s1.  Strcmp(s1,s2):- Compress s1 and s2 and returns –ve if s1<s2 , +ve if s1>s2 , 0 if s1=s2.
  • 7.
     Strcpy(s1,s2):- copiesthe string s2 into s1,modifying the string s1.  Strcmpi(s1,s2):- Compress s1 and s2 ignoring the case and return similar result as strcmp.  Strncmp(s1,s2,n):- compress the first n character of string s1 and s2 and return similar result as strcmp.  Strupr(s1):- Convert the string s1 to uppercase.
  • 8.
     Strchr(s1,c):- Returnsa pointer to the first occurrence of the character c in string s1.  Strrchr(s1,c):- Returns a pointer to the last occurrence of the character c in string s1.  Strstr(s1,s2):- Returns a pointer to the first occurrence of the string s2 in string s1.  Strrev(s1):- Returns the reverse string of string s1.
  • 9.
     Strtok(s1,s2):- Searchess1 for tokens that are separated by delimiters specified in s2. Returns the pointer to first char to first token in s1.  Steset(s1,c):- Sets all characters in string s1 to character c and quites when null character is detected.  Strnset(s1,c,n):- Sets the first char in string s1 to char c and quits when nill char is detected.  Sscanf:- Divided lines into tokens.