Write a C Program to Find Length of String using Pointers

What are Pointers?

A pointer is a variable whose value is the address of another variable, i.e., direct address of the memory location. Like any variable or constant, you must declare a pointer before using it to store any variable address.

The general form of a pointer variable declaration is −

• type *var-name;

Here, type is the pointer’s base type; it must be a valid C data type and var-name is the name of the pointer variable.

The asterisk * used to declare a pointer is the same asterisk used for multiplication. However, in this statement the asterisk is being used to designate a variable as a pointer.

The unary or monadic operator & gives the “address of a variable’”.

The indirection or dereference operator * gives the “contents of an object pointed to by a pointer”.

Below is the source code for C Program to Find Length of String using Pointers which is successfully compiled and run on Windows System to produce desired output as shown below :

SOURCE CODE : :

/*  C Program to Find Length of String using Pointers  */

#include<stdio.h>
#include<conio.h>

int string_ln(char*);

int main()
{
   char str[20];
   int length;

   printf("Enter any string :: ");
   scanf("%s",str);

   length = string_ln(str);
   printf("\nThe length of the given string [ %s ] is : %d\n", str, length);

  return 0;
}

int string_ln(char*p) /* p=&str[0] */
{
   int count = 0;
   while (*p != '\0') {
      count++;
      p++;
   }
   return count;
}

Output : : 

/*  C Program to Find Length of String using Pointers  */

Enter any string :: CodezClub

The length of the given string [ CodezClub ] is : 9

Process returned 0

Above is the source code for C Program to Find Length of String using Pointers which is successfully compiled and run on Windows System.The Output of the program is shown above .