help wid a program

[lionaneesh]

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

void reverse(char str[]);

int main()
{
    char str[100];
    int i;

    printf("Enter to reverse : ");
    scanf("%[^\n]",str);
    reverse(str);
    return(0);

}
/* Function */

void reverse(char str[])
{

    int i;
    for(i=(strlen(str));i > 0; i--)
    {
        printf("%c",str[i]);
    }
    putchar('\n');
}

in this programme when we input 123
output = 32 /* non - desired result 1 missing */

input = sonal , output = lano /* s missing*/

input = aneesh ,output = hseen /*a missing */

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

void reverse(char str[]);

int main()
{
    char str[100];
    int i;

    printf("Enter to reverse : ");
    scanf("%[^\n]",str);
    reverse(str);
    return(0);

}
/* Function */

void reverse(char str[])
{

    int i;
    for(i=(strlen(str));i >=0; i--)
    {
        printf("%c",str[i]);
    }
    putchar('\n');
}

in this program wen we input 123 the output is 231...
and:-
input = aneesh ,output = hseen
but by my understanding this for loop is wrong..

NOW the questions:-
1. Why in the first program the output in the case "123" is "32" and in case "aneesh" output is "hseen" ?

2. Why the second program provides right results despite the loop is wrong(by my understanding)?

[jonsca]

In your second example you haven't noticed the additional space that's being put in front of the word. This could very well be any junk character because when you reference str[strlen(str)] you overstep the bounds of the array. Remember, if your string is length 3 you're only going to have characters 0,1,2. So change that on line 23 to i = strlen(str) -1 and you'll have it right. You already figured out how you were missing the first element of the string when you had > instead of >=.

I would compliment you on a well written post (among all your other ones) but the title still needs work.

[lionaneesh]

In your second example you haven't noticed the additional space that's being put in front of the word. This could very well be any junk character because when you reference str[strlen(str)] you overstep the bounds of the array. Remember, if your string is length 3 you're only going to have characters 0,1,2. So change that on line 23 to i = strlen(str) -1 and you'll have it right. You already figured out how you were missing the first element of the string when you had > instead of >=.

I would compliment you on a well written post (among all your other ones) but the title still needs work.

Thank u Sir and i will improve my question next time thanks...

[lionaneesh]

In your second example you haven't noticed the additional space that's being put in front of the word. This could very well be any junk character because when you reference str[strlen(str)] you overstep the bounds of the array. Remember, if your string is length 3 you're only going to have characters 0,1,2. So change that on line 23 to i = strlen(str) -1 and you'll have it right. You already figured out how you were missing the first element of the string when you had > instead of >=.

I would compliment you on a well written post (among all your other ones) but the title still needs work.

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

void reverse(char str[]);

int main()
{
	char str[100];
	int i;

	printf("Enter to reverse : ");
	scanf("%[^\n]",str);
	reverse(str);
	return(0);

}
/* Function */

void reverse(char str[])
{

	int i;
	for(i=strlen(str)-1;i > 0; i--)
	{
		printf("%c",str[i]);
	}
	putchar('\n');
}

this again doesn't work....

[jonsca]

for(i=strlen(str)-1;i >= 0; i--) You needed both the -1 and the >=0. I had said you were on the right track with the >= sign, otherwise you lose the first character in the string.