Thread: How can I output an array backwards?

Code:

#include<stdio.h>
#include<stdlib.h>
int main()
{
 int  number[6],n;


	for (n=0; n<6; n++)
	{
	printf("\nEnter a number ");
	scanf("%d",&number[n]);
	printf("%d",number[n]);


 		if (number[n]==26)
 		{
 		printf("\nFound 26!");
 		break;
 		}
 	}


 return 0;
}

I need to input a list of six numbers into an array and output them backwards and if the number 26 is found, the values should stop printing.


Well I did everything except I do not know how to output them backwards. Any help would be appreciated.

Well I did everything except I do not know how to output them backwards.

Well, let's look at the code you already have.

Code:

for (n=0; n<6; n++)

So you start at "n = 0".
Then you increment 'n'.
And continue the loop until "n < 6".

So ... to print backwards ... perhaps you should start at the "end" and continue until the beginning.

And if you break out of your reading loop earlier than expected (i.e. you come across the value 26), you need some way to keep track of where the "end" is.

Originally Posted by Matticus

Well, let's look at the code you already have.

Code:

for (n=0; n<6; n++)

So you start at "n = 0".
Then you increment 'n'.
And continue the loop until "n < 6".

So ... to print backwards ... perhaps you should start at the "end" and continue until the beginning.

And if you break out of your reading loop earlier than expected (i.e. you come across the value 26), you need some way to keep track of where the "end" is.

So from what I am trying to understand, it has to be in this format?

Code:

for (n=6; n>6; n--)
{
printf("%d",number[n]);
}

Recall that arrays start at zero, and go to N-1. So for your declaration of "number[6]", the valid indices are 0 - 5.

Code:

for (n=6; n>6; n--)

So trying to access "number[6]" is out of bounds (hint: start at 5).
If you start "n" at 6 and decrease it, when is "n>6" ever true?
You're on the right track here.

Perhaps you should think about it a bit more, and try it out yourself in code. See what happens, see if you can figure it out, and ask specifically if you get stuck (and be sure to post updated code).

Originally Posted by Matticus

Recall that arrays start at zero, and go to N-1. So for your declaration of "number[6]", the valid indices are 0 - 5.

Code:

for (n=6; n>6; n--)

So trying to access "number[6]" is out of bounds (hint: start at 5).
If you start "n" at 6 and decrease it, when is "n>6" ever true?
You're on the right track here.

Perhaps you should think about it a bit more, and try it out yourself in code. See what happens, see if you can figure it out, and ask specifically if you get stuck (and be sure to post updated code).

THANK YOU! I got it working!