Hello guys, I have a question regarding Arrays

**Cdd101** · 10-04-2013

Originally Posted by SirPrattlepod

Yeah. Sorry

You're getting closer anyway

Code:

found = 0;
for (k = 0; k < ????; k++)    /* for every element of intersection[] */
{
    if (A[i] == intersection[k])
        found = 1;                /* A[i] is already in the intersection array */
}

if (found == 0)     /* if not already in intersection */
{
   ??????
}

Replace the ?????s with the correct code.

Note that there is an opportunity to exit the for loop early (as soon as a match is found) but I don't know if you've learned about the && operator or the break keyword yet.

Code:

found = 0;    for (k = 0; k < SIZE; k++)    /* for every element of intersection[] */
    {
        if (A[i] == intersection[k])
            found = 1;                /* A[i] is already in the intersection array */
    }


    if (found == 0)     /* if not already in intersection */
    {
        found=intersection[]+A[i];
        counter++;
    }

**SirPrattlepod** · 10-04-2013

In addendum to my previous post, it seems you're now writing almost random code hoping that *something* works instead of thinking about the problem and what your program is doing. I'm guessing that this is because you're getting stressed because of the deadline. Learn to deal with stress more constructively. Don't take offence at this observation it's something that's probably human nature and dealing with it effectively is a learned skill that takes practice.

**Cdd101** · 10-04-2013

Code:

#include <stdio.h>

#define SIZE 10
#define SIZE1 12


int main(void)
{
    int i;
    int j;
    int A[SIZE];
    int B[SIZE1];
    int intersection[SIZE];
    int counter = 0;
    int found;
    int k;


    for (i = 0; i < SIZE; i++)
    {
        printf("Enter number: ");
        scanf("%d", &A[i]);
    }
    for(i = 0; i < SIZE; i++)
    {
        printf("%d\n", A[i]);
    }
    for (i = 0; i < SIZE1; i++)
    {
        printf("Enter number: ");
        scanf("%d", &B[i]);
    }
    for(i = 0; i < SIZE1; i++)
    {
        printf("%d\n", B[i]);
    }


    for(i = 0; i < SIZE; i++)
    {
        for(j = 0; j < SIZE1; j++)
        {
            if (A[i] == B[j])
            {
                intersection[counter] = A[i];
                counter++;
            }
        }
    }


    found = 0;
    for (k = 0; k < SIZE; k++)    /* for every element of intersection[] */
    {
        if (A[i] == intersection[k])
            found = 1;                /* A[i] is already in the intersection array */
    }


    if (found == 0)     /* if not already in intersection */
    {
        found=intersection+A[i];
        counter++;
    }


    if (counter > 1)
    {
        printf("The intersection is: ");
        for(j = 0; j < counter; j++)
            printf("%d ", intersection[j]);
        printf("\n");
    }
    else
        printf("There is no intersection\n");


    return 0;
}

Hello guys, I have a question regarding Arrays-aaaaaaaa-png

Still does the same, must have messed up your code somewhere.

**Cdd101** · 10-04-2013

Originally Posted by SirPrattlepod

In addendum to my previous post, it seems you're now writing almost random code hoping that *something* works instead of thinking about the problem and what your program is doing. I'm guessing that this is because you're getting stressed because of the deadline. Learn to deal with stress more constructively. Don't take offence at this observation it's something that's probably human nature and dealing with it effectively is a learned skill that takes practice.

Honestly this is what is happening. I'll read up on your pseudocode before keeping posting nonsense. My bad pal.

**Adak** · 10-04-2013

If you need to print all the intersections, then you can use logic like this:

Code:

#include <stdio.h>

#define MAX7 7
#define MAX10 10

int main(void) {

   int i,j;
   int grid7[MAX7];
   int grid10[MAX10];

   for(i=0;i<MAX7;i++)
      grid7[i]=i;

   for(i=0;i<MAX10;i++)
      grid10[i]=i;

   for(i=0;i<MAX10;i++) {
      for(j=i;j<MAX7;j++) {  //this is key: j=i.
         if(grid10[i]==grid7[j])
            printf("%d \n",i);
      }
   }

   return 0;
}

Output:
0123456

Just one print out of each intersection

**SirPrattlepod** · 10-04-2013

Originally Posted by Cdd101

...
Still does the same, must have messed up your code somewhere.

Well that's almost it.

Code:

    found = 0;
    for (k = 0; k < SIZE; k++)    /* for every element of intersection[] */
    {
        if (A[i] == intersection[k])
            found = 1;                /* A[i] is already in the intersection array */
    }


    if (found == 0)     /* if not already in intersection */
    {
           intersection[counter] = A[i];                               // <----- FIXED THIS LINE
        counter++;
    }

The only other problem is you've put it in the wrong place. The snippet above should replace lines 45 and 46

**Cdd101** · 10-04-2013

Originally Posted by SirPrattlepod

Well that's almost it.

Code:

    found = 0;
    for (k = 0; k < SIZE; k++)    /* for every element of intersection[] */
    {
        if (A[i] == intersection[k])
            found = 1;                /* A[i] is already in the intersection array */
    }


    if (found == 0)     /* if not already in intersection */
    {
           intersection[counter] = A[i];                               // <----- FIXED THIS LINE
        counter++;
    }

The only other problem is you've put it in the wrong place. The snippet above should replace lines 45 and 46

Thank you so much pal

Code:

#include <stdio.h>

#define SIZE 10
#define SIZE1 12


int main(void)
{
    int i;
    int j;
    int A[SIZE];
    int B[SIZE1];
    int intersection[SIZE];
    int counter = 0;
    int found;
    int k;


    for (i = 0; i < SIZE; i++)
    {
        printf("Enter number: ");
        scanf("%d", &A[i]);
    }
    for(i = 0; i < SIZE; i++)
    {
        printf("%d\n", A[i]);
    }
    for (i = 0; i < SIZE1; i++)
    {
        printf("Enter number: ");
        scanf("%d", &B[i]);
    }
    for(i = 0; i < SIZE1; i++)
    {
        printf("%d\n", B[i]);
    }


    for(i = 0; i < SIZE; i++)
    {
        for(j = 0; j < SIZE1; j++)
        {
            if (A[i] == B[j])
            {
                intersection[counter] = A[i];
                counter++;
            }
        }
    }


    found = 0;
    for (k = 0; k < SIZE; k++)
    {
        if (A[i] == intersection[k])
            found = 1;
    }


    if (found == 0)
    {
        intersection[counter] = A[i];
        counter++;
    }


    if (counter > 1)
    {
        printf("The intersection is: ");
        for(j = 0; j < counter; j++)
            printf("%d ", intersection[j]);
        printf("\n");
    }
    else
        printf("There is no intersection\n");


    return 0;
}

This is the code and this is what it outputted this is fine. I'm tired of this assignment

Hello guys, I have a question regarding Arrays-capture-png

**SirPrattlepod** · 10-04-2013

Well, you're too close to get tired of it

Code:

#include <stdio.h>
 
#define SIZE 10
#define SIZE1 12
 
 
int main(void)
{
    int i;
    int j;
    int A[SIZE];
    int B[SIZE1];
    int intersection[SIZE];
    int counter = 0;
    int found;
    int k;
 
 
    for (i = 0; i < SIZE; i++)
    {
        printf("Enter number: ");
        scanf("%d", &A[i]);
    }
    for(i = 0; i < SIZE; i++)
    {
        printf("%d\n", A[i]);
    }
    for (i = 0; i < SIZE1; i++)
    {
        printf("Enter number: ");
        scanf("%d", &B[i]);
    }
    for(i = 0; i < SIZE1; i++)
    {
        printf("%d\n", B[i]);
    }
 
 
    for(i = 0; i < SIZE; i++)
    {
        for(j = 0; j < SIZE1; j++)
        {
            if (A[i] == B[j])
            {
                found = 0;
                for (k = 0; k < counter; k++)
                {
                    if (A[i] == intersection[k])
                        found = 1;
                }
                if (found == 0)
                {
                    intersection[counter] = A[i];
                    counter++;
                }
            }
        }
    }
 
    if (counter > 1)
    {
        printf("The intersection is: ");
        for(j = 0; j < counter; j++)
            printf("%d ", intersection[j]);
        printf("\n");
    }
    else
        printf("There is no intersection\n");
 
 
    return 0;
}

**Cdd101** · 10-04-2013

Originally Posted by SirPrattlepod

Well, you're too close to get tired of it

Code:

#include <stdio.h>
 
#define SIZE 10
#define SIZE1 12
 
 
int main(void)
{
    int i;
    int j;
    int A[SIZE];
    int B[SIZE1];
    int intersection[SIZE];
    int counter = 0;
    int found;
    int k;
 
 
    for (i = 0; i < SIZE; i++)
    {
        printf("Enter number: ");
        scanf("%d", &A[i]);
    }
    for(i = 0; i < SIZE; i++)
    {
        printf("%d\n", A[i]);
    }
    for (i = 0; i < SIZE1; i++)
    {
        printf("Enter number: ");
        scanf("%d", &B[i]);
    }
    for(i = 0; i < SIZE1; i++)
    {
        printf("%d\n", B[i]);
    }
 
 
    for(i = 0; i < SIZE; i++)
    {
        for(j = 0; j < SIZE1; j++)
        {
            if (A[i] == B[j])
            {
                found = 0;
                for (k = 0; k < counter; k++)
                {
                    if (A[i] == intersection[k])
                        found = 1;
                }
                if (found == 0)
                {
                    intersection[counter] = A[i];
                    counter++;
                }
            }
        }
    }
 
    if (counter > 1)
    {
        printf("The intersection is: ");
        for(j = 0; j < counter; j++)
            printf("%d ", intersection[j]);
        printf("\n");
    }
    else
        printf("There is no intersection\n");
 
 
    return 0;
}

Thank you so much! From what I see, the only difference from my code to yours was that you
united this

Code:

 for(i = 0; i < SIZE; i++)    {
        for(j = 0; j < SIZE1; j++)
        {
            if (A[i] == B[j])
            {
                found = 0;
                for (k = 0; k < counter; k++)
                {
                    if (A[i] == intersection[k])
                        found = 1;
                }
                if (found == 0)
                {
                    intersection[counter] = A[i];
                    counter++;
                }
            }
        }
    }

**SirPrattlepod** · 10-04-2013

Originally Posted by Cdd101

Thank you so much! From what I see, the only difference from my code to yours was that you
united this

Code:

 for(i = 0; i < SIZE; i++)    {
        for(j = 0; j < SIZE1; j++)
        {
            if (A[i] == B[j])
            {
                found = 0;
                for (k = 0; k < counter; k++)
                {
                    if (A[i] == intersection[k])
                        found = 1;
                }
                if (found == 0)
                {
                    intersection[counter] = A[i];
                    counter++;
                }
            }
        }
    }

Correct. I also fixed k < counter as the condition for the for loop.

You could exit the loop early (no need to keep checking if found is already 1) by changing the for loop to

Code:

for (k = 0; k < counter && found == 0; k++)

But only if you've learned about the && operator

After you've submitted your assignment please summarise what you've learnt.

The found variable, by the way, is referred to as a flag.

**Cdd101** · 10-05-2013

Originally Posted by SirPrattlepod

Correct. I also fixed k < counter as the condition for the for loop.

You could exit the loop early (no need to keep checking if found is already 1) by changing the for loop to

Code:

for (k = 0; k < counter && found == 0; k++)

But only if you've learned about the && operator

After you've submitted your assignment please summarise what you've learnt.

The found variable, by the way, is referred to as a flag.

What I learned from this assignment and it's something that has I've been wondering for a while is that you can do use a for, inside a for loop and an if as well. I always wondered about this since my teachers notes never had this on there. I'm extremely thankful for your help pal. Teachers notes have been to vague. His example programs, and definition don't really help when it comes to making each assignment.

**SirPrattlepod** · 10-05-2013

You've also learned that stress can make your mind dysfunctional and what a flag is

Stay calm.

I could have given you the code 9 hours ago but, well, what would you have learned then?

Edit: Oh, by the way, next weekend maybe try and write the program again. There are other ways to do it... see if you can make a better program. Hopefully you learn about functions soon and the code will be more readable as well. Good luck

**Cdd101** · 10-05-2013

Originally Posted by SirPrattlepod

You've also learned that stress can make your mind dysfunctional and what a flag is

Stay calm.

I could have given you the code 9 hours ago but, well, what would you have learned then?

Oh I was stressed, I was also doing a Java homework assignment earlier . Surprisingly find my Java class much more easier :|. Thank you, I'm very grateful for your help, I learned a lot from your help.

Since I really seem to struggle with my teachers notes would you recommend a book or something to learn from?