Output ',' between number fibonaci in c program - c

Question

#include<stdio.h>
int main()
{
int x, y = 0, z = 1, r, i;
scanf("%d",&x);
for ( i = 0 ; i < x ; i++ )
{
if ( i <= 1 )
z = i;
else
{
z = x + y;
x = y;
y = z;
}
printf("%d ",z);
}
return 0;
}
How to output a , between the numbers like this:
0, 1, 1, 2, 3, 5, 8, 13
I'll try hard but doesn't work. Maybe someone want's to help me.

Answer 1

The easiest way is to add additional printf for the ", " string under the condition that it is not the last for loop iteration
#include<stdio.h>
int main()
{
int x, y = 0, z = 1, r, i;
scanf("%d",&x);
for ( i = 0 ; i < x ; i++ )
{
if ( i <= 1 )
z = i;
else
{
z = x + y;
x = y;
y = z;
}
printf("%d",z);
if (i < x - 1) {
printf(", ");
}
}
return 0;
}

Answer 2

You have to additionally use printf(", "); as follows.
#include<stdio.h>
int main()
{
int x, y = 0, z = 1, r, i;
scanf("%d",&x);
for ( i = 0 ; i < x ; i++ )
{
if ( i <= 1 )
z = i;
else
{
z = x + y;
x = y;
y = z;
}
// Add comma if the print number is not first one
// You can also check by last index, but this is simple condition.
if( i != 0 )
{
printf(", ");
}
// Print number
printf("%d", z );
}
return 0;
}
For avoiding an unwanted comma, we have to handle this case according to the provided sample.

Answer 3

#include<stdio.h>
int main()
{
int x, y = 0, z = 1, r, i;
scanf("%d",&x);
for ( i = 0 ; i < x ; i++ )
{
if ( i <= 1 )
z = i;
else
{
z = x + y;
x = y;
y = z;
}
printf("%d",z);
if( i!=x-1 )
printf(", ");
}
return 0;
}

Answer 4

#include<stdio.h>
int main()
{
int x, y = 0, z = 1, r, i;
scanf("%d",&x);
char *separator = ""; /* this is the separator to be used between the numbers, initialized to the empty string */
for ( i = 0 ; i < x ; i++ )
{
if ( i <= 1 )
z = i;
else
{
z = x + y;
x = y;
y = z;
}
printf("%s%d", separator, z); /* take off the space after %d */
separator = ", "; /* after first number, we change the separator to a comma and an space */
}
printf("\n"); /* this is only recommended, to get a new line at the end */
return 0;
}
You can use this approach even if you don't know the kind of the indices or the data values you have to print in the loop.
Anyway, your program has other problems that I don't know if you want commented:
x is not initialized, so if you don't provide a correct number to scanf, you'll get undefined behaviour as it can have any value in the loop.
I think you use x for two purposes, as a limit on the number of fibonacci number to output, and as one of the adding numbers in the sequence, this is not correct. If you input something as 100 you'll not get the fibonacci numbers upto 100 because the x value is overwritten at the first iteration loop. Use something as limit instead.
I've let this points as exercises for you to complete, as you didn't asked about the wrong list that is output.