how to convert back to array

Sin Yee

hi...i finish my intersection now. I need to convert the output back to the array. I also need to arrange them in
the original form.
Before the intersection:
1 2
1 2 3
1 2 3 4
1 3
1 3 4
....

Now my output is like this:
2
1
2
1
3
2
1
3
4
1
3
1
3
4

i need to restore output in array and make them become like this:
my expected output that i want:
2 1
2 1 3
2 1 3 4
1 3
1 3 4
..
here is my coding:

for (int i = 0; i < myArray1.Count; i++)

{

foreach (string t in myArray1[i].ToString().Split(' '))

{

//ItemKey.AppendText(t);

hs3.Add(t);

}

var clone = new HashSet(hs2);

hs2.IntersectWith(hs3);

foreach (string y in hs2)

{

ItemKey.AppendText(y);

}

hs2 = clone;

hs3.Clear();

}

What should i need to do...to make my output become like this...hope someone can help me.thanks ya...

31 Replies

Know the answer? Post it — somebody with the same question will find it here.

Sin Yee15y ago
Thanks for helping....can run already....really sorry that i disturb you so much time.
Sin Yee15y ago
so this will start after the intersection?? i need to store my hs2 in the list and using this code to do the arrangement?
Vulpes15y ago
Anything you do before creating 'strarray' is irrelevant to the present exercise apart from what's finally in myArray1 and hs2 because that's now the starting point.

I've revised my code to start with exactly what you said you saw when you iterated through hs2 and myArray1 (the thread's got so long that I think I must have used some earlier stuff before):

using System;
using System.Collections.Generic;
using System.Windows.Forms;
using System.Linq;

class Test
{
   static void Main()
   {
   List myArray1 = new List();

   myArray1.Add("1 2");
   myArray1.Add("1 2 3");
   myArray1.Add("1 2 3 4");
   myArray1.Add("1 2 4");
   myArray1.Add("1 3");
   myArray1.Add("1 3 4");
   myArray1.Add("1 4");
   myArray1.Add("2 3");
   myArray1.Add("2 3 4");
   myArray1.Add("2 4");
   myArray1.Add("2 5");
   myArray1.Add("3 4");

   List hs2 = new List();

   hs2.Add("2");
   hs2.Add("1");
   hs2.Add("2");
   hs2.Add("1");
   hs2.Add("3");
   hs2.Add("2");
   hs2.Add("1");
   hs2.Add("3");
   hs2.Add("4");
   hs2.Add("2");
   hs2.Add("1");
   hs2.Add("4");
   hs2.Add("1");
   hs2.Add("3");
   hs2.Add("1");
   hs2.Add("3");
   hs2.Add("4");
   hs2.Add("1");
   hs2.Add("4");
   hs2.Add("2");
   hs2.Add("3");
   hs2.Add("2");
   hs2.Add("3");
   hs2.Add("4");
   hs2.Add("2");
   hs2.Add("4");
   hs2.Add("2");
   hs2.Add("5");
   hs2.Add("3");
   hs2.Add("4");

   string[] strarry = hs2.ToArray();

   string[] myArray2 = new string[myArray1.Count];
   int[] lens = new int[myArray1.Count];
   int index = 0;

   foreach (string y in myArray1)
   {
   lens[index] = y.Replace(" ", "").Length;
   index++;
   }

   index = 0;
   int index2 =0;

   string[] temp = new string[lens[0]];

   foreach (string q in strarry)
   {
   if (index2 < lens[index])
   {
   temp[index2] = q;
   index2++;
   }
   else
   {
   myArray2[index] = String.Join(" ", temp);
   index++;
   temp = new string[lens[index]];
   temp[0] = q;
   index2 = 1;
   }
   }

   myArray2[index] = String.Join(" ", temp);

   string message = String.Join("\r\n", myArray2);
   MessageBox.Show(message);
   }
}

The output is now :

2 1
2 1 3
2 1 3 4
2 1 4
1 3
1 3 4
1 4
2 3
2 3 4
2 4
2 5
3 4

which is exactly what you said you were expecting.
Sin Yee15y ago
I had tried your code. But the result still the same as the previous one
Sin Yee15y ago
//single key and item
HashSeths1 = new HashSet();

var g = from k in sItem.Keys
orderby sItem[k] descending
select k;

foreach (var k in g)
{
//display3 += k + ":" + sItem[k] + "\r\n";
SingleSupport.AppendText(k + ":" + sItem[k] + "\r\n");
hs1.Add(k);
}

//key and values for comabination
ArrayList myArray1 = new ArrayList();
string text = "";
IDictionaryEnumerator et = itemS.GetEnumerator();
while (et.MoveNext())
{
KeyitemS.AppendText(et.Key.ToString() + ":" + et.Value.ToString() + "\r\n");
myArray1.Add(et.Key.ToString());
}

HashSet hs2 = new HashSet(hs1);
HashSet hs3 = new HashSet();

for (int i = 0; i < myArray1.Count; i++)
{
foreach (string t in myArray1[i].ToString().Split(' '))
{
hs3.Add(t);
}

var clone = new HashSet(hs2);

hs2.IntersectWith(hs3);

string[] myArray2 = new string[myArray1.Count];

hs2 = clone;
hs3.Clear();

this is the code that i used to do my intersection
the hs1 is store the single item key and value that already sorted from highest to lowest based on the values.
2:8
1:7
3:7
4:7
5:1

the myArray1 is store the key of combination
1 2
1 2 3
1 2 3 4
1 2 4
1 3
1 3 4
1 4
2 3
2 3 4
2 4
2 5
3 4

i need to do the intersection with these two.
hs3 is store the item from myArray1 after split.
hs2 is store the hs1. after each of the intersection it will reset and intersect with the hs3. hs3 will be cleared after each intersection to store the new next line item.
After that i need to convert back to array and display the output like this
2 1
2 1 3
2 1 3 4
2 1 4
1 3
1 3 4
1 4
2 3
2 3 4
2 4
2 5
3 4
...
this is the output that i want....
Vulpes15y ago
Yes, I do.

But, anyway, I've extracted both the data and the code into a console app so we can see exactly what's going on. I've had to use a List for hs2, to avoid the duplicates being lost, but otherwise the code is essentially the same as before:

using System;
using System.Collections.Generic;
using System.Windows.Forms;
using System.Linq;

class Test
{
   static void Main()
   {
   List myArray1 = new List();

   myArray1.Add("1 2");
   myArray1.Add("1 2 3");
   myArray1.Add("1 2 3 4");
   myArray1.Add("1 3");
   myArray1.Add("1 3 4");
   myArray1.Add("1 4"); // guess
   myArray1.Add("2 3"); // guess
   myArray1.Add("2 3 4"); // guess
   myArray1.Add("3 4"); // guess

   List hs2 = new List();

   hs2.Add("2");
   hs2.Add("1");
   hs2.Add("2");
   hs2.Add("1");
   hs2.Add("3");
   hs2.Add("2");
   hs2.Add("1");
   hs2.Add("3");
   hs2.Add("4");
   hs2.Add("2");
   hs2.Add("1");
   hs2.Add("4");
   hs2.Add("2");
   hs2.Add("3");
   hs2.Add("2");
   hs2.Add("3");
   hs2.Add("4");
   hs2.Add("2");
   hs2.Add("4");
   hs2.Add("2");
   hs2.Add("5");
   hs2.Add("3");
   hs2.Add("4");

   string[] strarry = hs2.ToArray();

   string[] myArray2 = new string[myArray1.Count];
   int[] lens = new int[myArray1.Count];
   int index = 0;

   foreach (string y in myArray1)
   {
   lens[index] = y.Replace(" ", "").Length;
   index++;
   }

   index = 0;
   int index2 =0;

   string[] temp = new string[lens[0]];

   foreach (string q in strarry)
   {
   if (index2 < lens[index])
   {
   temp[index2] = q;
   index2++;
   }
   else
   {
   myArray2[index] = String.Join(" ", temp);
   index++;
   temp = new string[lens[index]];
   temp[0] = q;
   index2 = 1;
   }
   }

   myArray2[index] = String.Join(" ", temp);

   string message = String.Join("\r\n", myArray2);
   MessageBox.Show(message);
   }
}

The output is:

2 1
2 1 3
2 1 3 4
2 1
4 2 3
2 3
4 2
4 2 5
3 4

which looks OK to me.
Sin Yee15y ago
You mean put after the intersection statement..?
Sin Yee15y ago
string text = "";
foreach (string q in hs2)
{
text += q.Length.ToString() + "\r\n";
}
MessageBox.Show(text);

output:
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1

string text = "";
foreach (string q in myArray1)
{
text += q + "\r\n";
}
MessageBox.Show(text);

output:
12 times loops for
1 2
1 2 3
1 2 3 4
1 2 4
1 3
1 3 4
1 4
2 3
2 3 4
2 4
2 5
3 4
Vulpes15y ago
Well, as that's full of duplicates, then there are three possibilities:-

1. hs2 is not a HashSet but something else which has an IntersectWith method.

2. The items in the HashSet contain variable amounts of whitespace after the digit.

3. I'm going completely mad!

I'm tending at the moment towards option #3 but then I can't understand why the code using strarray isn't working.

Can you change the previous code snippet slightly to this and tell me again what you see:

string text = "";
foreach (string q in hs2)
{
text += q.Length.ToString() + "\r\n";
}
MessageBox.Show(text);

And then finally, do this one as well, so we're absolutely sure what we've got:

string text = "";
foreach (string q in myArray1)
{
text += q + "\r\n";
}
MessageBox.Show(text);
Sin Yee15y ago
the output is
2
1
2
1
3
2
1
3
4
2
1
4
1
3
1
3
4
1
4
2
3
2
3
4
2
4
2
5
3
4
Vulpes15y ago
We seem to be going around in circles here.

OK, tell me exactly what you see when you run this piece of code immediately after the intersection:

string text = "";
foreach (string q in hs2)
{
text += q + "\r\n";
}
MessageBox.Show(text);
Sin Yee15y ago
i need to convert the output of intersection to array and display like the previous one after intersect with the hs3....
Sin Yee15y ago
'2121321342141313423234242534' this is the output after the intersection(hs2.IntersectWith(hs3)).I need to use these output to display like the previous style.
Vulpes15y ago
That won't help at all because strarry contains the same elements as hs2.

What I need to know is where is '2121321342141313423234242534' stored?

You said in your last but two post that it was stored in a string array but what's the name of the array because I can't see it in your code?
Sin Yee15y ago
if i change the 'strarry ' to hs2..?

   for (int i = 0; i < myArray1.Count; i++)
   {
   foreach (string t in myArray1[i].ToString().Split(' '))
   {
   hs3.Add(t);
   }

   var clone = new HashSet(hs2);

   hs2.IntersectWith(hs3);

   string[] myArray2 = new string[myArray1.Count];
   int[] lens = new int[myArray1.Count];
   int index = 0;

   foreach (string y in myArray1)
   {
   lens[index] = y.Replace(" ", "").Length;
   index++;
   }

   index = 0;
   int index2 = 0;

   string[] temp = new string[lens[0]];

   foreach (string q in hs2)
   {
   if (index2 < lens[index])
   {
   temp[index2] = q.ToString();
   index2++;
   }
   else
   {
   myArray2[index] = String.Join(" ", temp);
   index++;
   temp = new string[lens[index]];
   temp[0] = q.ToString();
   index2 = 1;
   }

   }
   myArray2[index] = String.Join(" ", temp);
   ItemKey.AppendText(String.Join("\r\n", myArray2));

   hs2 = clone;
   hs3.Clear();

   }
Vulpes15y ago
As I said in my previous post, the problem is that 'strarry' doesn't contain your output (which contains duplicates) because it's derived from a hashset (which can't contain duplicates).

So, where is your code which stores and, presumably prints out, your output?

If I could see that, then I should be able to figure out what changes are needed to make this work.
Sin Yee15y ago
here is the code....pls help me see ..where i got wrong...
String[] strarry;

   for (int i = 0; i < myArray1.Count; i++)
   {
   foreach (string t in myArray1[i].ToString().Split(' '))
   {
   hs3.Add(t);
   }

   var clone = new HashSet(hs2);

   hs2.IntersectWith(hs3);

   strarry = hs2.ToArray();

   string[] myArray2 = new string[myArray1.Count];
   int[] lens = new int[myArray1.Count];
   int index = 0;

   foreach (string y in myArray1)
   {
   lens[index] = y.Replace(" ", "").Length;
   index++;
   }
   index = 0;
   int index2 =0;

   string[] temp = new string[lens[0]];

   foreach (string q in strarry)
   {
   if (index2 < lens[index])
   {
   temp[index2] = q;
   index2++;
   }
   else
   {
   myArray2[index] = String.Join(" ", temp);
   index++;
   temp = new string[lens[index]];
   temp[0] = q;
   index2 = 1;
   }
   }

   myArray2[index] = String.Join(" ", temp);
   ItemKey.AppendText(String.Join("\r\n", myArray2));

   hs2 = clone;
   hs3.Clear();
   }
Sin Yee15y ago
yaya...now can display already but the output seem very weird...
is like this:
2 1

2 1
3

2 1
3 4

....and so on...
the output that i hold before i do this arrangement is 2121321342141313423234242534 (in string array)
not in vertical
2
1
2
1
3
2
1
3
4
2
1
4
2
3
2
3
4
2
4
2
5
3
4
How to solve this problem..Sorry that i trouble you...But i am newbie for c#.So hope you can help me.
Vulpes15y ago
It's such a muddle that it's difficult to know where to start but I can see right away that you've missed out the highlighted line:

foreach (string y in myArray1)
{
lens[index] = y.Replace(" ", "").Length;
index++;
}

Also there's no way that strarray can contain your 'output' values bearing in mind that they contain duplicates. That's because you've derived strarray from the hashset, hs2, which can't possibly contain any duplicates as they're removed automatically as elements are added.
Sin Yee15y ago
temp[0] = q.ToString(); this line give the error....what should i do..???
Sin Yee15y ago
temp[0] = q.ToString(); this line give the error....
Sin Yee15y ago
pls help me see see my code...
Sin Yee15y ago
i still dont understand where i got wrong....??
here is the code...
String [] Array = new string[myArray1.Count];
String[] strarry;
for (int i = 0; i < myArray1.Count; i++)
{
foreach (string t in myArray1[i].ToString().Split(' '))
{
//ItemKey.AppendText(t);
hs3.Add(t);
}

var clone = new HashSet(hs2);

hs2.IntersectWith(hs3); // intersection

strarry = hs2.ToArray(); //store back to array

string[] myArray2 = new string[myArray1.Count];
int[] lens = new int[myArray1.Count];
int index = 0;
foreach (string y in myArray1)
{
lens[index] = y.Replace(" ", "").Length;
}
index = 0;
int index2 = 0;
string[] temp = new string[lens[0]];

foreach (string q in strarry)
{
if (index2 < lens[index])
{
temp[index2] = q.ToString();
index2++;
}
else
{
myArray2[index] = String.Join(" ", temp);
index++;
temp = new string[lens[index]];
temp[0] = q.ToString();
index2 = 1;
}
}
myArray2[index] = String.Join(" ", temp);
ItemKey.AppendText(String.Join("\r\n", myArray2));

hs2 = clone;
hs3.Clear();
}
Vulpes15y ago
strings, string arrays or string lists know nothing about whether they're displayed horizontally or vertically.

If the output is stored in a string array rather than a simple string, then my first attempt should work as there's no difference between iterating through an array or a list when using foreach.

As long as there were 14 digits in the original list before the intersection and there are 14 elements in the output string array, then the length shouldn't be a problem.

What the code is doing is working out the length of each string in the original list and storing it in the 'lens' array. It then counts off the appropriate number of digits from the output array, separates them with spaces and then inserts the result in myArray2.
Sin Yee15y ago
is it the length problem....??
Sin Yee15y ago
still the same error...is it because now my output is in horizontal form and store in string array not in vertical form???
Vulpes15y ago
If the output is in the form of a string rather than a list, then change the second foreach() statement to the following:

foreach(char y in output)
{
   if (index2 < lens[index])
   {
   temp[index2] = y.ToString();
   index2++;
   }
   else
   {
   myArray2[index] = String.Join(" ", temp);
   index++;
   temp = new string[lens[index]];
   temp[0] = y.ToString();
   index2 = 1;
   }
}
Sin Yee15y ago
got error...it just can print out first one output then will give the error said"index was outside bound of array"...
Sin Yee15y ago
sorry for wrong post my output that i hold now is like this: 21213213413134
Sin Yee15y ago
sorry for wrong post my output that i hold now is like this: 21213213413134
Vulpes15y ago
Well, it's not clear to me from that code where the original form is stored or where the output is stored. Assuming that the former is stored in a list called 'original' and the latter in a list called 'output', then this code should convert 'output' into an array in the original form and display it in a MessageBox:

string[] myArray2 = new string[original.Count];
int[] lens = new int[original.Count];
int index = 0;

foreach(string y in original)
{
   lens[index] = y.Replace(" ", "").Length;
   index++;
}

index = 0;
int index2 = 0;

string[] temp = new string[lens[0]];

foreach(string y in output)
{
   if (index2 < lens[index])
   {
   temp[index2] = y;
   index2++;
   }
   else
   {
   myArray2[index] = String.Join(" ", temp);
   index++;
   temp = new string[lens[index]];
   temp[0] = y;
   index2 = 1;
   }
}

myArray2[index] = String.Join(" ", temp); // do last one

MessageBox.Show(String.Join("\r\n", myArray2));