can't understand the increment used here...

[shiv_d]

whats the reason behind usin' another (i = i + 1) in the 2nd 'for loop'?
i'm very new at C,and i posted this at another forum but didn't quite get a good enough answer, so pls go easy on me! thanks!!

#include <stdio.h>

main()
{
char first[21];
char sur[21];
char buffer[42];
int i, j;

printf("Please enter your first name: ");
fflush(stdin);
scanf("%[^\n]", first);
printf("Please enter your last name: ");
fflush(stdin);
scanf("%[^\n]", sur);

/*
* First, copy the first name into the buffer, a la strcpy()

*/
for (i = 0; first[i] != '\0'; i = i + 1)
buffer[i] = first[i];

/*
* Add the space
*/
buffer[i] = ' ';
i = i + 1; /* don't forget to adjust the counter */

/*
* Next, concatentate the surname onto the buffer, a la strcat()
* Notice that the for loop has TWO increments
*/
for (j = 0; sur[j] != '\0'; j = j + 1, i = i + 1)
buffer[i] = sur[j];
buffer[i] = '\0'; /* don't forget to terminate the string */

printf("The full name is >>%s<<\n", buffer);

fflush(stdin);
getchar();
}

[Quantum1024]

j is used as the index into the 'sur' array while i is used as the index into the 'buffer' array.
When 'first' was copied to 'buffer the same index value could be used because first[0] was copied to buffer[0], first[1] to buffer[1] and so on. But when coppying from the 'sur' array the program is adding to the buffer array from the current possition not starting from the start.

[Salem]

> whats the reason behind usin' another (i = i + 1) in the 2nd 'for loop'?
Well you can try it without, and observe the difference.

Also, read the FAQ and figure out why fflush(stdin) is bad.

[sand_man]

Every iteration, i is incremented as well as j. Simple as that.

[shiv_d]

thanks all you guys!!!

Quantum1024 -i like your answer the most, thats what i couldn't understand before!! thanks a ton!!

Salem - i tried without it and it didn't print anythin' after the space-char. but i couldn't understand it before...i do now!thanks for the heads-up for fflush(stdin), i'll check it out!