Saturday, 3 March 2018

String In C

String is a collection of characters or array of characters and it is terminated by \0 (null character).
<string.h> header file is used in String C programming.
There are two ways to declare string in c, they are
1.     By char array
2.     By string literal
1) string by char array 
char str[20]={'H''E''L', 'L','O','\0'};    
Array index starts from 0.So it is represented like this

Example:
 #include<stdio.h> 
      #include<string.h> 
      #include<conio.h> 

      void main(){   
      char str[20]={'H', 'E', 'L', 'L','O','\0'};   
   
      printf("Char Array Value is: %s\n",str);   
       getch();
       }   
     Output:
Char Array Value is: HELLO
 
 2) string By string literal:
char str[20]="HELLO";    
Example:
#include<stdio.h>  
    #include <string.h>  
    #include<conio.h>  
    void main(){    
   char str[20]="HELLO";    
    
   printf("String Literal Value is: %s\n", str);    
   getch();
       }    
Output:
String Literal Value is: HELLO  

gets() and puts() functions
gets() function reads string from user(input) and puts() function prints the string(output).
Example:
     #include<stdio.h> 
     #include <string.h> 
     #include<conio.h> 
      void main(){   
     char name[30];   
    printf("Enter  name: ");   
    gets(name); //input
    printf("Name is: ");   
    puts(name);  //displays or print string   
   getch();
       }
Output:
Enter  name: suryosnata                                                                                                        
Name is: suryosnata  


strlen() function

strlen() function returns the length of the given string. It doesn't count null character '\0'.
Example:
    #include<stdio.h> 
   #include <string.h>
   #include<conio.h> 
   void main(){   
   char str[20]={'s', 'u', 'r', 'y', 'o', 's', 'n', 'a', 't', 'a', '\0'};   
   printf("Length of string is: %d",strlen(str));   
   getch();   
}   
  Output:
 Length of string is: 10

   Copy String:strcpy()
    strcpy() function copies the source string in destination.
    Syntax:
    strcpy(destination, source)
     
     Example:
#include<stdio.h> 
 #include <string.h>   
 #include<conio.h>
void main(){   
char str[20]={'s', 'u', 'r', 'y', 'o', 's', 'n', 'a', 't', 'a', '\0'};   
   char str2[20];   
   strcpy(str2,str);   
   printf("Copied string is: %s",str2);   
getch();
Output:

Copied string is: suryosnata

String Concatenation:strcat()
strcat()function concatenates two strings .
Syntax:
strcat(first_string, second_string);
Example:
#include<stdio.h> 
#include <string.h>   
#include<conio.h>
void main(){   
  char str[20]={'s', 'u', 'r', 'y', 'o', 's', 'n', 'a', 't', 'a', '\0'};   
   char str2[10]={'B','e','h','e','r','a','\0'};   
   strcat(str,str2);   
   printf("New String is:%s",str);   
  getch();   
}   
Output:
   New String is:suryosnataBehera 

 

Compare String:strcmp()

strcmp() function compares two string and returns 0 if both strings are equal.
Syntax:
strcmp(first_string, second_string)
Example:
#include<stdio.h> 
#include <string.h>
#include<conio.h>  
  void main(){   
  char str1[20],str2[20];   
  printf("Enter 1st string: ");   
  gets(str1);
  printf("Enter 2nd string: ");   
  gets(str2);
  if(strcmp(str1,str2)==0) 
      printf("Strings are equal");   
}
  else   
{
      printf("Strings are not equal");  
}
getch();
}  
Output:
Enter 1st string: suryosnata                                                                                                   
Enter 2nd string: suryosnata                                                                                                   
Strings are equal 

 

Reverse String:strrev()

strrev(string) function returns reverse of the given string.
Example:
#include<stdio.h> 
#include <string.h>   
#include<conio.h>
  void main(){   
  char str[20];   
  printf("Enter string: ");   
  gets(str);
  printf("String is: %s",str);   
  printf("\nReverse String is: %s",strrev(str));   
getch();   
}
Output:
Enter string:suryosnata
String is: suryosnata 
Reverse String is: atansoyrus

String Lowercase:strlwr()
strlwr(string) function returns string characters in lowercase.
   Example:
    #include<stdio.h> 
    #include <string.h>   
    #include<conio.h>
   void main(){   
  char str[20];   
  printf("Enter string: ");   
  gets(str);
  printf("String is: %s",str);    
  printf("\nLower String is: %s",strlwr(str));   
getch();
}   
Output:
Enter string: SURYOsnata
String is: SURYOsnata
Lower String is:suryosnata

String Uppercase:strupr()
strupr(string) function returns string characters in uppercase.
Example:
#include<stdio.h> 
#include <string.h>   
 #include<conio.h>
 void main(){   
  char str[20];   
  printf("Enter string: ");   
  gets(str);
  printf("String is: %s",str);   
  printf("\nLower String is: %s",strupr(str));   
getch();
}   
Output:
Enter string: SURYOsnata
String is: SURYOsnata
Lower String is:SURYOSNATA
 

 

No comments:

Post a Comment

apply function in R

1) apply function: It takes 3 arguments matrix,margin and function.. Example: m<-matrix(c(1,2,3,4),nrow=2,ncol=2) m #1 indicates it is ap...