Strlen

[NavyBlue]

How do I find the number of alphanumeric in a string?

[planet_abhi]

i think u r very newbie to prog


Use strlen function
Syntax: strlen(string);

[datainjector]

Originally posted by NavyBlue
How do I find the number of alphanumeric in a string?

This is how you use strlen

#include <stdio.h>
#include <string.h>

int main()
{
        char name[] = "Datainjector";

        printf( "Your string is %lu long\", strlen(name));
        return 0;
}

[Hammer]

>>alphanumeric
... would suggest you can't use strlen(), as this will include all characters up the \0. Maybe you don't want non-alpha numerics counted.

Maybe you need to write your own version, and use something like isalnum().

[sundeeptuteja]

Try this.

#include<ctype.h>
#include<stdio.h>
#include<string.h>
#include<conio.h>
int main()
{
   int ctr,ctr2;   
   char string[]="Sample String";
   ctr2=0;
   for(ctr=0; ctr<strlen(string); ++ctr)
   {
      if(isalnum(string[ctr]))
         ++ctr2;
   }
   printf("The number of alphanumeric characters is %d.",ctr2);
   getch();
   return(0);
}

Compiler : Turbo C++ v1.01.

[Hammer]

>>char string[]="Sample String";
string is a reserved name, therefore you shouldn't use it.

>>for(ctr=0; ctr<strlen(string); ++ctr)
Checking the length of the string everytime you go round the loop isn't helping efficiency. It'd be better to store the length in a variable and use that to control the loop.

[sundeeptuteja]

The program seems to work fine on Turbo C++ v1.01, as a C source file. Are you sure string is a reserved name? I am relatively new to C, just a first year college student.

[Hammer]

>>The program seems to work fine on Turbo C++ v1.01, as a C source file.
That maybe so, but it doesn't make it correct as per the C Standard.

>>Are you sure string is a reserved name?
Yes, or I would not have said so.