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How to concatenate two strings without using strcat?

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How to concatenate two strings without using strcat?

Mar 19th, 2007

Q.Write a function to concatenate to input strings into one large string and display the result.

I know how to do this using strcat but not without it. Also can't use pointers. Please help!!

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Re: How to concatenate two strings without using strcat?

Mar 19th, 2007

hi it is very easy find the length of the first character array, and find the length of the second character array, using a loop concodinate both strings.
i dont know it is correct or not

char str1[],str2[];
int l1,l2;

l1=length(str1);
l2=length(str2);

for(i=0 ;i<str2;i++)
str1[l1+i]=str2[i];

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Re: How to concatenate two strings without using strcat?

Mar 19th, 2007

>i dont know it is correct or not
It's not. Why don't you test out thing on your compiler first before posting them?

To concatenate a string, remember that strings are basically arrays of characters. This means that you can loop through the arrays (or strings) and copy letters into another one. First of all, create an array that's the combined length of both strings (plus 1 for the terminating null character). Then simply start by copying the first string into the array, and then proceed by doing the same to the other.

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Re: How to concatenate two strings without using strcat?

Mar 20th, 2007

 Help with Code Tags 
 C Syntax (Toggle Plain Text) 
/* myconcat.c */
 
#include <stdio.h>
 
int main(void)
{
    char first_s[] = "Hello";
    char second_s[] = "World";
    int i = 0;
    int x = 0;
 
    char long_s[sizeof(first_s) + sizeof(second_s)];
 
    while(first_s[i])
    {
        long_s[i] = first_s[i];
        ++i;
    }
    long_s[i] = ' ';
    ++i;
 
    while(second_s[x])
    {
        long_s[i] = second_s[x];
        ++i;
        ++x;
    }
    long_s[i] = '\0'; /* don't forget the null */
 
    printf(long_s);
    putchar('\n');
 
    getchar();
    return 0;
}
/* myconcat.c */

#include <stdio.h>

int main(void)
{
    char first_s[] = "Hello";
    char second_s[] = "World";
    int i = 0;
    int x = 0;
    
    char long_s[sizeof(first_s) + sizeof(second_s)];

    while(first_s[i])
    {
        long_s[i] = first_s[i];
        ++i;
    }
    long_s[i] = ' ';
    ++i;
    
    while(second_s[x])
    {
        long_s[i] = second_s[x];
        ++i;
        ++x;
    }
    long_s[i] = '\0'; /* don't forget the null */
    
    printf(long_s);
    putchar('\n');
    
    getchar();
    return 0;
}

If you want to learn something more advanced, do read this little snippet by Dave Sinkula.

http://www.daniweb.com/code/snippet406.html

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Re: How to concatenate two strings without using strcat?

Mar 21st, 2007

Hey I got it..i did it differently though..thnx neways

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Re: How to concatenate two strings without using strcat?

Mar 22nd, 2007

sorry i am now using vb very much but i have used c only 2 years befor. i was in a cafe so i was unable to compile the program...

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Re: How to concatenate two strings without using strcat?

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Feb 3rd, 2009

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Originally Posted by zigpy_siva

sorry i am now using vb very much but i have used c only 2 years befor. i was in a cafe so i was unable to compile the program...

#include<stdio.h>
#include<conio.h>
#include<string.h>
void main()
{
char str1[30],str2[30];
int l1,l2,i;
clrscr();
gets(str1);
gets(str2);
l1=strlen(str1);
l2=strlen(str2);

for(i=0;i<=l2;i++)
{
str1[l1+i]=str2[i];
}
printf("%s",str1);
}

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Re: How to concatenate two strings without using strcat?

Feb 3rd, 2009

Or u could use a Linked List to put the first string in a List and put the second string in another list .
Then u can link the two lists together to get A concatenated string

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Re: How to concatenate two strings without using strcat?

Feb 3rd, 2009

•

Originally Posted by saswata

#include<stdio.h>
#include<conio.h>
#include<string.h>
void main()
{
char str1[30],str2[30];
int l1,l2,i;
clrscr();
gets(str1);
gets(str2);
l1=strlen(str1);
l2=strlen(str2);

for(i=0;i<=l2;i++)
{
str1[l1+i]=str2[i];
}
printf("%s",str1);
}

The main function always returns an integer when hosted by an operating system. So void main() is not acceptable.
gets() is not acceptable neither, for different reason. It can not be stop of reading more that buffer can support, without overflow.
#include<conio.h> and clrscr(); are none portable, therefore voids the "warranty". Furthermore, clearing the screen is a doubtful practice, for the sake of "prettiness".
Next time use the expected code tags to post source code. Here's an example.

"If it moves, tax it. If it keeps moving, regulate it, and if it stops moving, subsidize it" - Ronald Reagan