23 - WAP to implement strlen (), strcat (),strcpy () using the concept of Functions.

WAP to implement strlen (), strcat (),strcpy () using the concept of Functions.

1. Length of the string (strlen)
The syntax of strlen is :

strlen(string);

It calculates the length of the string and returns its length. For example:
 

#include<string.h>

string = "Mumbai";

printf("Length = %d",strlen(string));

The above code displays 5, because Mumbai consists of 5 characters. Note: it does not count null character.

2. Joining two strings (strcat)

The syntax of strcat is

strcat(string1,string2);

Now it removes the null character from string1 and joins the first character of string2 at that position. Now string1 consists of both string1 and string2 in joined form. Example:
 

#include<string.h>

char string1[] = "Anti";

char string2[] = "Particle";

strcat(string1,string2);

printf("%s",string1); //display AntiParticle

3. Comparing two strings(strcmp)

The syntax of strcmp is

strcmp(string1,string2);

It returns 0 if string1 is same as string2 and returns 1 if they are not same. Example:
 

#include<string.h>

char string1 = "Nepal";

char string2 = "Srilanka";

if(strcmp(string1,string2)==0){

printf("They are equal");

}else{

printf("They are not equal"); //this is executed

}

4. Copying one string to another (strcpy)

The syntax of strcpy is 
 

strcpy(destination_string, source_string);

It copies the content of source_string to destination_string. Example:
 

#include<string.h>

char source[] = "Hello";

char destination[10]; //uninitialized

strcpy(destination,source);

printf("%s",destination); //prints Hello