Question

Why does my array print differently just by simply adding a useless printf?

Answer 1

By having that printf statement, my code prints out the correct sorted array. without it, it acts weird. I read something about it not being synchronized, but how do i fix that?

Answer 2

@wio

Answer 3

any ideas wio? i've been stuck on this for so loong. :( also i need help writing an assembly method that gets the min value from an array. but this problem is my main focus rn.

Answer 4

I'm not sure. I don't see how the print statement would change anything.

Answer 5

should i take a screen shot
of the different messages?

Answer 6

somewhere on stackoverflow it said that the printf has a synchonized(this) in its actual code. so, it lets the thread know it's the same.

Answer 7

and without it, the variables stay separate and get cached or something.

Answer 8

http://meta.stackoverflow.com/questions/269174/questions-about-threadloop-not-working-without-print-statement << this was the post. howeve,r i can't fix it evne reading this.

Answer 9

You're not using Java though, right?

Also, are you doing a multi-threaded program?

Answer 10

i'm not sure. what is meant by a multithreaded program. i'm doing c.

Answer 11

I'm calling the insert functions many times, yes.

Answer 12

If it is a single threaded program, you don't need to worry about syncronization.

Answer 13

how do i know if it is multi-threaded prog?

Answer 14

It will create a thread. Something like pthread in C

Answer 15

well it seems like i am running a multi-threaded program then. i don't know where it says pthread, but it's not wokring without the print statement.

Answer 16

wait, would you happen to know how ot write basic assembly code?

Answer 17

If you haven't learned about threads yet, then you shouldn't be having a synchronization issue in your class.

Answer 18

we learned about threads in previous classes, but nothing was mentioned about it in this one.

Answer 19

but um, i'll try to figure this out. However, i really need help with writing an assembly code that gets the min value from an array. i know how to do arithmetic operations. however i do not know how to do get teh value. Any help?

Answer 20

I can help you come up with a better insert function.

Answer 21

ok!

Answer 22

```
void resize(list *ls) {
ls->maxSize = ls->maxSize * 2;
ls->sortedList = (int *) realloc(ls->sortedList);
}

int insert(list *ls, int val) {
int position; // insert position
int i; // index used for shifting array
if (ls->size == ls->maxSize) {
resize(ls);
}

// find the insertion position
for (position= 0; position < ls->size; position++) {
if (ls->sortedList[position] > val) {
break;
}
}

// shift the elements after insertion points over
for (i = ls->size; i > position; i--) {
ls->sortedList[i + 1] = ls->sortedList[i];
}

// set array value
ls->sortedList[position] = val;
ls->size++;
return position;
}

```
You shouldn't check for a pointer to be `null`. Ultimately, you should never pass a null pointer into a function which requires a non-null value.

Answer 23

Hmmm, I think one line I put was wrong.
```
ls->sortedList[i + 1] = ls->sortedList[i];
```
Should be
```
ls->sortedList[i] = ls->sortedList[i - 1];
```

Answer 24

You should create a new question for your assembly thing.

Answer 25

ok!