C Program to find length of string without using Library function

[Basavaraj]

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1. #include<stdio.h>  
2. #include<conio.h>  
3. void main()  
4. {  
5.   int length( char *p ); // Function prototype.  
6.   char *ptr;  // char pointer to read the string.  
7.   int len;    // variable in which length is stored.  
8.   clrscr();  
9.   printf("Enter a string : ");  
10.   gets( ptr ); // reading string from keyboard  
11.   len=length( ptr ); // string is passed as argument to function( funcation call)  
12.   printf("Length of string is : %d",len); // displaying the result.  
13.   getch();  
14.   
15. }  
16.   
17.   
18. int length( char *p )  // Function definition  
19. {  
20.   int len=0;  
21.     
22.   while( *p )  
23.   {  
24.   len++;  
25.   p++;  
26.   }  
27.   return(len);  
28.   
29. }  

#include<stdio.h>
#include<conio.h>
void main()
{
  int length( char *p ); // Function prototype.
  char *ptr;  // char pointer to read the string.
  int len;    // variable in which length is stored.
  clrscr();
  printf("Enter a string : ");
  gets( ptr ); // reading string from keyboard
  len=length( ptr ); // string is passed as argument to function( funcation call)
  printf("Length of string is : %d",len); // displaying the result.
  getch();

}


int length( char *p )  // Function definition
{
  int len=0;
  
  while( *p )
  {
  len++;
  p++;
  }
  return(len);

}

This problem is solved by defining out own function to find the length of string. here i have used char pointer to read the string.
using the concept of pointer we could solve the problem easily.

the while loop while( *P ) { len++; } gets executed repeatedly until it encounters null char which is usually present at the end of the string. the *p is written to fetch char from its pointer it is known as indirection operator,after fetching the char the pointer is incremented using the statement p++ which will make the pointer to point to the next char.

[Satish]

Sir, edit the post and use these syntax to format it to look better.

Syntax For Writing Your Program Code On This Forum

don’t forget about the < and > replacement strings of html while writing the code.

[Author]

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