c# - Finding combinations from a list of objects and sorting them according to property value -

i have list of type cardslot, each of these cardslot objects contain different cards , , card1, card2, card3 (the number may differ).

each cardslot object has maximum quantity of card1, card2 , card3 pre-set. now, user inputs amount of cards required , should combination of cardslot fulfill criteria.

for eg:

 list<cardslot> listcardslot = new list<cardslot>();  cardslot cardslot1 = new cardslot();  cardslot1.name = "cardslot1";  cardslot1.price = 900;  cardslot1.card1 = 2;  cardslot1.card2 = 3;  cardslot1.card3 = 4;  listcardslot.add(cardslot1);   cardslot cardslot2 = new cardslot();  cardslot2.name = "cardslot2";  cardslot2.price = 850;  cardslot2.card1 = 3;  cardslot2.card2 = 2;  cardslot2.card3 = 4;  listcardslot.add(cardslot2);   cardslot cardslot3 = new cardslot();  cardslot3.name = "cardslot3";  cardslot3.price = 950;  cardslot3.card1 = 4;  cardslot3.card2 = 3;  cardslot3.card3 = 2;  listcardslot.add(cardslot3); 

now, if user inputs card1 = 4, card2 = 5 , card3 = 4, end result should combination of cardslot objects least possible price.

can please give me nudge in right direction?kindly tell me if unclear , i'll try , improve it.

edit

i have tried finding possible combinations can in list using following function:

public static list<list<t>> itemcombinations<t>(list<t> inputlist, int minimumitems = 1)     {         int nonemptycombinations = (int)math.pow(2, inputlist.count) - 1;         list<list<t>> listofcombinations = new list<list<t>>(nonemptycombinations + 1);          if (minimumitems == 0)               listofcombinations.add(new list<t>());          (int = 1; <= nonemptycombinations; i++)         {             list<t> thiscombination = new list<t>(inputlist.count);             (int j = 0; j < inputlist.count; j++)             {                 if ((i >> j) % 2 != 0)                     thiscombination.add(inputlist[j]);             }              if (thiscombination.count >= minimumitems)                 listofcombinations.add(thiscombination);         }          return listofcombinations;     } 

this returns possible combinations. however, still not take care of situations repeated occurance of same card slot may correct choice. e.g in above mentioned scenario correct choice 1 x cardslot1 + 1 x cardslot2

edit 2

i reached intermediate solution , have posted answer, still not give me required answer in case of mix , match combinations. take , suggest towards end ?

so have made solution this, must it's headburn me, have tried something.

cardslot class made:

public class cardslot {     public string name { get; set; } = "";     public double price { get; set; } = 0;     public int card1 { get; set; } = 0;     public int card2 { get; set; } = 0;     public int card3 { get; set; } = 0; } 

and rest follows as:

  //your code   //as above   //in question   listcardslot.add(cardslot3); //your code    valuechecker(1);    double lowestamount = mycards.any() ? mycards.min(item => item.price) : 0;    messagebox.show("you need " + multiplier.tostring() + " " +                     returnlowestcardslot(lowestamount).name); }  int = 4, b = 5, c = 4; //user entered values  int multiplier = 0;  list<cardslot> mycards = new list<cardslot>(); cardslot returnlowestcardslot(double lowestprice) {     cardslot cardslot = null;     foreach (var item in mycards)     {         if (item.price == lowestprice)         {             cardslot = item;             break;         }     }     return cardslot; }  void valuechecker(int increment) {     multiplier += increment;     foreach (cardslot item in listcardslot)     {         if (((multiplier * item.card1) >= a) &&             ((multiplier * item.card2) >= b) &&              ((multiplier * item.card3) >= c))         {             if (!(mycards.contains(item)))                 mycards.add(item);         }     }     if (mycards.count == 0)        valuechecker(1);   } 

the output i'm getting is:

you need 2 cardslot1

hope tweak 1 somehow fit need

edit
see want output 2 cardslot2 has :

cardslot2.card1 = 3; cardslot2.card2 = 2; cardslot2.card3 = 4; 

2 x cardslot2 give:

cardslot2.card1 = 6; cardslot2.card2 = 4; cardslot2.card3 = 8; 

but user's requirement usercard1 = 4 , usercard1 = 5 & usercard1 = 4.
here card2 = 4 still lesser usercard2 = 5
don't see how fulfils requirement.

edit 2

your comment right, didn't though of that. give result:

  //codes same   //as question   valuechecker(1);    double lowestamount = mycards.any() ? mycards.min(item => item.price) : 0;    cardslot leastcard = returnlowestcardslot(lowestamount, mycards);    double lowestamount2 = listcardslot.any() ? listcardslot.min(item => item.price) : 0;    cardslot lowestcard = returnlowestcardslot(lowestamount2, listcardslot);    if ((leastcard.price + lowestcard.price) > (multiplier * leastcard.price))        messagebox.show("you need " + multiplier.tostring() + " " + leastcard.name);    else        messagebox.show("you need 1 " + leastcard.name + " , 1 " + lowestcard.name); } 

and modified returnlowestcardslot

cardslot returnlowestcardslot(double lowestprice, list<cardslot> list) {     cardslot cardslot = null;     foreach (var item in list)     {         if (item.price == lowestprice)         {             cardslot = item;             break;         }     }     return cardslot; } 

output:

you need 1 cardslot1 , 1 cardslot2