Cracking the Coding Interview Chapter 3 Solutions in PeopleCode

#1

Function createMultiStack Returns array of array of string
 
   Local array of array of string &multiStack;
   Local array of string &lineData;
   Local File &dataFile;
   Local string &holder;
 
   &triple = CreateArrayRept(CreateArrayRept("", 0), 0);
   &lineData = CreateArrayRept("", 0);
 
   &dataFile = GetFile("names_phones_emails.csv", "R");
   While &dataFile.ReadLine(&holder);
      &lineData = Split(&holder, ",");
      &triple [1].push(&lineData [1]);
      &triple [2].push(&lineData [2]);
      &triple [3].push(&lineData [3]);
   End-While;
 
   For &I = 0 To &triple.Len
      &holder = &triple [1][&I] | " " | &triple [2][&I] | " " | &triple [3][&I];
      MessageBox(0, "", 0, 0, &holder);
   End-For;
 
   Return &triple;
 
End-Function;

#2

/* For every pop or push the min part of the array needs to be
    checked and reinitialized when needed */

Function stackWithMin Returns array of array of number
 
   Local array of array of number &stackWithMin;
   Local array of number &findMin;
   Local File &dataFile;
   Local string &holder;
   Local number &index;
 
   &stackWithMin = CreateArrayRept(CreateArrayRept(0, 0), 0);
   &findMin = CreateArrayRept(0, 0);
   &dataFile = GetFile("numbers.txt", "R");
 
   While &dataFile.ReadLine(&holder)
      &stackWithMin.Push(Value(&holder));
      &findMin.Push(Value(&holder));
   End-While;
 
   &findMin.Sort("A");
   &index = 0;
 
   While &stackWithMin.Next(&index);
      &stackWithMin [&index].Push(&findMin [1]);
   End-While;
 
   Return &stackWithMin;
 
End-Function;

#3

class stackSet
   method stackSet();
 
   method sspush(&pushItem As number);
   method sspop() Returns number;
   method sspeek() Returns number;
   method popAt(&targetStack As number) Returns number;
   property number threshhold get set;
 
private
   instance array of array of number &ss;
   instance number &itemcount;
   instance number &stackcount;
 
end-class;

method stackSet
   %This.threshhold = 10;
   %This.ss = CreateArrayRept(CreateArrayRept(0, 10), 0);
   %This.itemcount = 0;
   %This.stackcount = 0;
end-method;


method sspush
   /+ &pushItem as Number +/
   If %This.itemcount = 0 And
         %This.stackcount = 0 Then
      %This.itemcount = 1;
      %This.stackcount = 1;
   Else
      If %This.itemcount < %This.threshhold Then
         %This.itemcount = %This.itemcount + 1;
      Else
         %This.stackcount = %This.stackcount + 1;
         %This.itemcount = 1;
      End-If;
   End-If;
   %This.ss [%This.stackcount].Push(&pushItem);
end-method;

method sspop
   /+ Returns Number +/
   Local number &prevCount = %This.itemcount;
   If %This.itemcount = 1 Then
      If %This.stackcount > 1 Then
         %This.itemcount = %This.threshhold;
         %This.stackcount = %This.stackcount - 1;
      Else
         %This.itemcount = 0;
         %This.stackcount = 0;
      End-If
   Else
      If %This.itemcount > 1 Then
         %This.itemcount = %This.itemcount - 1;
      End-If;
   End-If;
   If &prevCount > 0 Then
      Return %This.ss [%This.stackcount].Pop();
   End-If;
end-method;

method sspeek
   /+ Returns Number +/
   Local number &peekval;
   &peekval = %This.ss [%This.stackcount][%This.itemcount];
   Return &peekval;
end-method;

method popAt
   /+ &targetStack as Number +/
   /+ Returns Number +/
   Local number &targetItem, &holdItem, &I;
 
   If &targetStack > 0 Then
      If &targetStack = %This.stackcount Then
         Return %This.sspop();
      End-If;
      If &targetStack < %This.stackcount Then
         &targetItem = %This.ss [&targetStack].Pop();
       
         For &I = &targetStack + 1 To %This.stackcount Step 1
            &holdItem = %This.ss [&I].Shift();
            %This.ss [&I - 1].Push(&holdItem);
         End-For;
         If %This.itemcount = 1 Then
            %This.itemcount = %This.threshhold;
            %This.stackcount = %This.stackcount - 1;
         Else
            %This.itemcount = &itemcount - 1;
         End-If;
         Return &targetItem;
      End-If;
   End-If;
end-method;

get threshhold
   /+ Returns Number +/
   Return %This.threshhold;
end-get;

set threshhold
   /+ &NewValue as Number +/
   %This.threshhold = &NewValue;
   %This.ss = CreateArrayRept(CreateArrayRept(0, &NewValue), 0);
end-set;

#4

class qW2stack
   method qW2stack();
   method firstIn(&inItem As number);
   method firstOut() Returns number;
   method firstPeek() Returns number;
 
private
   instance array of number &putStack;
   instance array of number &viewStack;
 
end-class;

method qW2stack
   %This.putStack = CreateArrayRept(0, 0);
   %This.viewStack = CreateArrayRept(0, 0);
end-method;

method firstIn
   /+ &inItem as Number +/
   %This.putStack.Push(&inItem);
end-method;

method firstOut
   /+ Returns Number +/
   Local number &item, &I, &J;
   If %This.putStack.Len > 0 Then
      For &I = 1 To %This.putStack.Len
         %This.viewStack.Push(%This.putStack.Pop());
      End-For;
      &item = %This.viewStack.Pop();
      For &J = 1 To %This.viewStack.Len
         %This.putStack.Push(%This.viewStack.Pop());
      End-For;
      Return &item;
   End-If;
end-method;

method firstPeek
   /+ Returns Number +/
   Local number &item, &I, &J;
   If %This.putStack.Len > 0 Then
      For &I = 1 To %This.putStack.Len
         %This.viewStack.Push(%This.putStack.Pop());
      End-For;
      &item = %This.viewStack.Pop();
      %This.putStack.Push(&item);
      For &J = 1 To %This.viewStack.Len
         %This.putStack.Push(%This.viewStack.Pop());
      End-For;
      Return &item;
   End-If;
end-method;

#5

Function sortDescending(&stackArray As array of number)
 
   &stackArray.Sort("D");
 
End-Function;

#6

Function animalShelter(&choice As string, &dogQ As array of datetime, &catQ As array of datetime) Returns datetime
 
   &dogQ.Sort("A");
   &catQ.Sort("A");
 
   Evaluate &choice
   When "O"
      If &dogQ [1] < &catQ [1] Then
         Return &dogQ.Shift();
      Else
         Return &catQ.Shift();
      End-If;
      Break;
   When "D"
      Return &dogQ.Shift();
      Break;
   When "C"
      Return &catQ.Shift();
      Break;
   End-Evaluate;
 
End-Function;