Develop Reference

Trying to get all possible combinations from an unknown number of list of strings

Given a list of lists I am looking to create all possible combinations.
Example:
I have a list which holds 3 lists
List 1: Apple, Banana, Pear
List 2: Bed, Chair
List 3: Ben, Bob, Carl, Phil
From this I would expect to end up with a List of combinations
Apple_Bed_Ben
Apple_Bed_Bob
Apple_Bed_Carl
Apple_Bed_Phil
Apple_Chair_Ben
Apple_Chair_Bob
Apple_Chair_Carl
Apple_Chair_Phil
Banana_Bed_Ben
Banana_Bed_Bob
...
I don't know if I am missing something but I have been going in circles for hours now.
If I knew there would only ever be three lists I know I could just use nested for loops going through building the combination string but here there could be any number of lists.
Can anyone point me in the right direction to get this done?
This is what i currently have:
public class ChildrenNames
{
public string parentName;
public int numberOfNames;
public List<string> childrenNames = new List<string>();
}
public class Combination
{
public bool selected = true;
public string name;
}
List<Combination> GetAllCombinations()
{
List<Combination> allCombinations = new List<Combination>();
List<ChildrenNames> listOfChildren = new List<ChildrenNames>();
//Create list of children names for each parent object
for (int p = 0; p < parentObjects.Count; p++)
{
ChildrenNames cn = new ChildrenNames();
for (int c = 0; c < parentObjects[p].transform.childCount; c++)
cn.childrenNames.Add(parentObjects[p].transform.GetChild(c).name);
cn.parentName = parentObjects[p].name;
cn.numberOfNames = cn.childrenNames.Count;
listOfChildren.Add(cn);
}
for (int l = 0; l < listOfChildren.Count; l++)
{
for (int c = 0; c < listOfChildren[l].numberOfNames; c++)
{
if (l == 0)
{
for (int p = 0; p < listOfChildren.Count; p ++)
{
Combination combination = new Combination();
combination.name = listOfChildren[l].childrenNames[c];
allCombinations.Add(combination);
}
}
else
{
for (int i = 0; i < allCombinations.Count; i++)
allCombinations[i].name += "_" + listOfChildren[l].childrenNames[c];
}
}
}
return allCombinations;
}
This creates the correct number of combinations but for example throws out
Apple_Bed_Chair_Ben_Bob_Carl_Phil
I understand why this is happening but not how I can change this to get the expected result.

You need to keep track of the column for each of the lists in order for it to work properly.
public List<string> ZipStringLists(params List<string>[] lists)
{
var columnNo = new int[lists.Length];
var resultingList = new List<string>();
var stringBuilder = new StringBuilder();
while (columnNo[0] < lists[0].Count)
{
// Combine the items into one: Apple + Banana + Pear = AppleBananaPear
for (int i = 0; i < lists.Length; i++)
{
var listElement = lists[i];
// columnNo[i] contains which column to write out for the individual list
stringBuilder.Append(listElement[columnNo[i]]);
}
// Write out the result and add it to a result list for later retrieval
var result = stringBuilder.ToString();
resultingList.Add(result);
Console.WriteLine(result);
stringBuilder.Clear();
// We increment columnNo from the right to the left
// The next item after AppleBedBen is AppleBedBob
// Overflow to the next column happens when a column reaches its maximum value
for (int i = lists.Length - 1; i >= 0; i--)
{
if (++columnNo[i] == lists[i].Count
&& i != 0 /* The last column overflows when the computation finishes */)
{
// Begin with 0 again on overflow and continue to add to the next column
columnNo[i] = 0;
}
else
{
// No overflow -> stop
break;
}
}
}
return resultingList;
}
Usage:
List<string> list1 = new List<string> { "Apple", "Banana", "Pear" };
List<string> list2 = new List<string> { "Bed", "Chair" };
List<string> list3 = new List<string> { "Ben", "Bob", "Carl", "Phil" };
ZipStringLists(list1, list2, list3);

You could use a fairly generic solution that accepts any number of lists to incrementally build up the combinations. It's short, though not necessarily as optimal as other solutions as it builds intermediate lists:
public List<string> FindCombinations(params List<string>[] lists)
{
List<string> combinations = lists[0];
for (int i = 1; i < lists.Length; i++)
{
List<string> newCombinations = new List<string>(combinations.Count * lists[i].Count);
combinations.ForEach(s1 => lists[i].ForEach(s2 => newCombinations.Add($"{s1}_{s2}")));
combinations = newCombinations;
}
return combinations;
}
Usage:
List<string> combinations = FindCombinations(list1, list2, list3, list4, list5...)

name is not incrementing by 1 after number 45

i am trying to add a location name to my output text files.
As you can see my numbers are incrementing properly. But i have coded like after number 45 i need to reset the number to 1, also the Carousel:45 should change to ** Carousel1:1**. But it is not happening... why it is not happening. any help please!!!!
My code snippet:
public void just_create_text()
{
//Here we are exporting header
string[] strLines = System.IO.File.ReadAllLines(textBox1.Text);
string CarouselName = enter.Text;
int[] cols = new int[] { 15, 15, 25, 15, 15 };
StringBuilder sb = new StringBuilder();
string line = RemoveWhiteSpace(strLines[0]).Trim();
string[] cells = line.Replace("\"", "").Split('\t');
for (int c = 0; c < cells.Length; c++)
sb.Append(cells[c].Replace(" ", "_").PadRight(cols[c]));
sb.AppendLine("Location".PadRight(15));
sb.AppendLine();
int tmpCarousel = 0;
int carouselNumber = 0;
Dictionary<string, int> namesForCarousels = new Dictionary<string, int>();
for (int i = 0; i < textfile.Count; i++)
{
for (int c = 0; c < cells.Length; c++)
sb.Append(textfile[i].Cells[c].Replace(" ", "_").PadRight(cols[c]));
string name = textfile[i].Cells[1];
if (namesForCarousels.TryGetValue(name, out tmpCarousel) == false)
{
carouselNumber++;
if (carouselNumber > 45)
carouselNumber = 1;//resetting to number1, but name is
//not changing to Carousel1..
namesForCarousels[name] = carouselNumber;
}
var strCorousel = lstMX.Find(x => x.MAX_PN.Equals(name)).Carousel;
strCorousel = (String.IsNullOrEmpty(strCorousel)) ? CarouselName : strCorousel;
sb.Append(String.Format("{0}:{1}", strCorousel, carouselNumber).PadRight(15));
sb.Append("\r\n");
}
System.IO.File.WriteAllText(#"Z:\Desktop\output.TXT", sb.ToString());
}
OUTPUT i need
I need after Carousel:45 >>> i need Carousel1:1. How can i do this..?

You never use the numbers stored in your dictionary namesForCarousels after setting them. Probably you want
sb.Append(String.Format("{0}:{1}", strCorousel, namesForCarousels[name]).PadRight(15));
Also, you should rename carouselNumber to something like carouselNumberCounter. It's not the number of the current carousel, it's a counter used to assign a number to the next carousel. And for additional clarity, get rid of the local variable tmpCarousel and do:
if (!namesForCarousels.ContainsKey(name))
{

You might find it easier to follow your code if you use more descriptive variable names. It's not entirely clear what you're trying to do, but I assume you want to re-use the same carousel number for a given "Max Pn" if you've already allocated it - at the moment, you populate that mapping but you don't use it, you are reliant on max pn being in order. I don't actually see why carousel number wouldn't reset, but if you tidy it up perhaps you have a better chance of seeing what is happening.
Also given your null reference exception from your other question, this protects against that - though it probably indicates another problem elsewhere in the population of your "lstMx".
public static void just_create_text()
{
//Here we are exporting header
string[] strLines = System.IO.File.ReadAllLines(textBox1.Text);
string defaultCarouselName = enter.Text;
int[] columnPaddings = new int[] { 15, 15, 25, 15, 15 };
StringBuilder completedOutputBuilder = new StringBuilder();
string line = RemoveWhiteSpace(strLines[0]).Trim();
string[] cells = line.Replace("\"", "").Split('\t');
for (int c = 0; c < cells.Length; c++)
completedOutputBuilder.Append(cells[c].Replace(" ", "_").PadRight(columnPaddings[c]));
completedOutputBuilder.AppendLine("Location".PadRight(15));
completedOutputBuilder.AppendLine();
int carouselNumberForEntry = 0;
Dictionary<string, int> maxPnToCarouselNumber = new Dictionary<string, int>(StringComparer.OrdinalIgnoreCase);
for (int i = 0; i < textfile.Count; i++)
{
for (int c = 0; c < cells.Length; c++)
completedOutputBuilder.Append(_textfile[i].Cells[c].Replace(" ", "_").PadRight(columnPaddings[c]));
string maxPnForEntry = textfile[i].Cells[1];
int previouslyAllocatedCarouselNumberForMaxPn = 0;
if (maxPnToCarouselNumber.TryGetValue(maxPnForEntry, out previouslyAllocatedCarouselNumberForMaxPn) == false)
{
// assign a new courousel number for this max pn
carouselNumberForEntry++;
if (carouselNumberForEntry > 45)
carouselNumberForEntry = 1;
// for better clarity use add
maxPnToCarouselNumber.Add(maxPnForEntry, carouselNumberForEntry);
}
else
{
// use the carousel number previous assigned for this maxPn
carouselNumberForEntry = previouslyAllocatedCarouselNumberForMaxPn;
}
// find the related max pn carousel entry (if relatedPn is not found this suggests a problem elsewhere)
MAX_PN_Carousel relatedPn = lstMx.Find(x => x.MAX_PN != null && x.MAX_PN.Equals(maxPnForEntry, StringComparison.OrdinalIgnoreCase));
// assign the name from the entry, or use the default carousel name if unavailable
string carouselNameForMaxPn = (relatedPn == null || String.IsNullOrWhiteSpace(relatedPn.Carousel)) ? defaultCarouselName : relatedPn.Carousel;
// add the new column in the output
completedOutputBuilder.Append(String.Format("{0}:{1}", carouselNameForMaxPn, carouselNumberForEntry).PadRight(15));
completedOutputBuilder.Append("\r\n");
}
System.IO.File.WriteAllText(#"c:\dev\output.TXT", completedOutputBuilder.ToString());
}

Textbox to array declaration in C# windows form

Hi I’m fairly new to c# programming so please bear with me. I’m currently working on a “simple” little program which allows the user to enter 25 values into the same text box and once this has been done I want to be able to display this 25 values in a list box as an array of 5 row by 5 column and I want to find out the largest number in the array.
private void button1_Click(object sender, EventArgs e)
{
int arrayrows = 5;
int arraycolomns = 5;
int[,] arraytimes;
arraytimes = new int[array rows, array columns];
// list_Matrix.Items.Add(tb_First.Text);
for (int i = 0; i != 5; i++)
{
for (int j = 0; j != 5; j++)
{
array times [i,j]= Convert. To Int32(Tb_First.Text);
list_Matrix.Items.Add(array times[i, j].To String());
}
}
}
This is what I've tried for displaying the array in a list box, but it isn't working. This also prevents me from moving to the next section of finding the largest number among them.

You can split your string using .Split(' ') (or any other character or string). This will give you a onedimensional array with 25 elements (if everything was entered). The trick to converting that into a twodimensional array or grid is to use integer division and modulo, the following code would to
String[] splitText = textBox.Text.Split(' '); //gets your 25-length 1D array
//make an empty grid with the right dimensions first
int[][] grid = new int[5][];
for (int i=0;i<5;i++) {
grid[i] = new int[5];
}
//save our highest value
int maxVal = 0;
//then fill this grid
for (int i=0;i<splitText.Length;i++){
int value = int.Parse(splitText[i]);
//i%5 gives us values from 0 to 4, which is our 'x-coordinate' in the grid
//i/5 uses integer division so its the same as Math.floor(i/5.0), giving us your 'y-coordinates'
grid[i%5][i/5] = value;
//check if this value is larger than the one that is currently the largest
if (value > maxVal)
{
maxVal = value;
}
}
This will fill the twodimensional grid array with the split textbox text, and if there are not enough values in the textbox it leaves a 0 in those cells.
At the end you will also have your maximum value.

Try the following (shows by printing the numbers as string). and assuming you enter the numbers in the following way,
'1,2,3,4...'
string[] nums=txtBox.Text.Split(',');
lstBox.Items.Clear();
int colCount=5;
int colIndex=0;
string line="";
foreach(string num in nums)
{
if(colIndex==colCount)
{
lstBox.Items.Add(line);
line="";
colIndex=0;
}
line+= line==""? num : " "+num;
colIndex+=1;
}
if(line!="")
lstBox.Items.Add(line);
Make sure to correct any syntax mistakes, and to change the parameter names to yours.

private void button1_Click(object sender, EventArgs e)
{
int[] ab=new int[10];
string s = textBox1.Text;
int j = 0;
string [] a = (s.Split(' '));
foreach (string word in a)
{
ab[j] = Convert.ToInt32(word);
j++;
}
for (int i = 0; i < 10; i++)
{
label2.Text +=ab[i].ToString()+" ";
}
}

Put multiple values in an array

I have a issue that i cant solve.
Here is the code
sik input = new sik();
for (int i = 0; i < 5; i ++)
{
input.skId = securitiesArray[i].skId;
input.country = securitiesArray[i].country;
}
sik[] inputs = new sik[]
{
input
};
Now i know this will only put 1 value in the sik[] list.
How can i put all the 5 values in this list.
Thanks
Note: i cannot initialize ski[] first. This has to be done in that order.

Any reason that it has to be an array?
List<sik> input = new List<sik>();
for (int i = 0; i < 5; i ++)
{
var newInput = new sik();
newInput.skId = securitiesArray[i].skId;
newInput.country = securitiesArray[i].country;
input.Add(newInput);
}
The reason that the List is useful is that it can dynamically grow with you, so you have no need to worry about how many instances you may need to add.
MSDN Documentation for List and all of it's glorious methods
http://msdn.microsoft.com/en-us/library/6sh2ey19.aspx

sik[] inputs = new sik[5];
for (int i = 0; i < 5; i ++)
{
sik input = new sik();
input.skId = securitiesArray[i].skId;
input.country = securitiesArray[i].country;
inputs[i] = input;
}

You can use Linq to do this.
sik[] inputs = securitiesArray.Select(item =>
new sik()
{
skId = item.skId,
country = item.country
}).ToArray();

You can't have variable size array, instead you can use List.
List<sik> siks = new List<sik>();
sik input = new sik();
for (int i = 0; i < 5; i ++)
{
input.skId = securitiesArray[i].skId;
input.country = securitiesArray[i].country;
siks.Add(input);
}
If you want array yet, use sik[] inputs = skis.ToArray();

You can also do this,
List<sik> input=new List<sik>();
for(int i=0;i<securitiesArray.Length;i++)
{
input.Add(new{skId=securitiesArray[i].skid,country=securitiesArray[i].country});
}

For what it's worth, here the Linq approach:
sik[] inputs = Enumerable.Range(0, 5)
.Select(i => new sik{ kId = securitiesArray[i].skId, country = securitiesArray[i].country})
.ToArray();
If securitiesArray is of type sik(the properties suggest), you can select directly from it:
sik[] inputs = securitiesArray.Take(5).ToArray();

Array of string not working

I use a simple array: contentHouseOne[] that contains strings. But in the Do/While loop it isn't working! It seems like the code don't understand that it's a string when a new object is to be created!? It works when I hardcode the string like I show below. Help is preciated! Thanks!
This isn't working:
listHouseParts.Add(new HousePart(content, contentHouseOne[i], newPosition));
But this works:
listHouseParts.Add(new HousePart(content, "100x100", newPosition));
EDIT:
Here are some code to declare arrays
string[] contentHouseOne = new string[] { "ruta100x100Red",
"ruta100x100Grey",
"ruta100x100Green",
"ruta100x100Yellow",
"ruta100x100Blue" };
bool[,] occupiedPositions = new bool[500,500];
Here are some code to set all grid positions to false
for (int i = 0; i < gridCol; i++)
for (int ii = 0; ii < gridRow; ii++)
occupiedPositions[i, ii] = false;
And finally here are the code that I have the problem
int i = 0;
do
{
Vector2 newPosition = NewRandomPosition;
if (occupiedPositions[(int)newPosition.X, (int)newPosition.Y] == false)
{
listHouseParts.Add(new HousePart(content,
contentHouseOne[i], newPosition));
occupiedPositions[(int)newPosition.X, (int)newPosition.Y] = true;
i++;
}
}
while (i <= 5);

Your string array includes five elements:
string[] contentHouseOne = new string[] { "ruta100x100Red",
"ruta100x100Grey",
"ruta100x100Green",
"ruta100x100Yellow",
"ruta100x100Blue" };
But your while loop ends if your running variable i is greater than 5
while (i <= 5);
which causes a IndexOutOfBounds exception on contentHouseOne, because the 6th element at index 5 isn't defined.
You should change your while condition to (i < 5).

Try this so atleast you know if its empty or not
HousePart housePart = new HousePart();
housePart.Content = content;
if (!string.IsNullOrEmpty(contentHouseOne[i]))
housePart.ContentHouseOne = contentHouseOne[i];
else
housePart.ContentHouseOne = string.Empty;
housePart.NewPosition = newPosition;
listHouseParts.Add(housePart);