Initial data commit

Task/Associative-array-Creation/BASIC256/associative-array-creation.basic

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+global values$, keys$
+dim values$[1]
+dim keys$[1]
+
+call updateKey("a","apple")
+call updateKey("b","banana")
+call updateKey("c","cucumber")
+
+gosub show
+
+print "I like to eat a " + getValue$("c") + " on my salad."
+
+call deleteKey("b")
+call updateKey("c","carrot")
+call updateKey("e","endive")
+gosub show
+
+end
+
+show:
+for t = 0 to countKeys()-1
+   print getKeyByIndex$(t) + " " + getValueByIndex$(t)
+next t
+print
+return
+
+subroutine updateKey(key$, value$)
+   # update or add an item
+   i=findKey(key$)
+   if i=-1 then
+      i = freeKey()
+      keys$[i] = key$
+   end if
+   values$[i] = value$
+end subroutine
+
+subroutine deleteKey(key$)
+   # delete by clearing the key
+   i=findKey(key$)
+   if i<>-1 then
+      keys$[i] = ""
+   end if
+end subroutine
+
+function freeKey()
+   # find index of a free element in the array
+   for n = 0 to keys$[?]-1
+      if keys$[n]="" then return n
+   next n
+   redim keys$[n+1]
+   redim values$[n+1]
+   return n
+end function
+
+function findKey(key$)
+   # return index or -1 if not found
+   for n = 0 to keys$[?]-1
+      if key$=keys$[n] then return n
+   next n
+   return -1
+end function
+
+function getValue$(key$)
+   # return a value by the key or "" if not existing
+   i=findKey(key$)
+   if i=-1 then
+      return ""
+   end if
+   return values$[i]
+end function
+
+function countKeys()
+   # return number of items
+   # remember to skip the empty keys (deleted ones)
+   k = 0
+   for n = 0 to keys$[?] -1
+      if keys$[n]<>"" then k++
+   next n
+   return k
+end function
+
+function getValueByIndex$(i)
+   # get a value by the index
+   # remember to skip the empty keys (deleted ones)
+   k = 0
+   for n = 0 to keys$[?] -1
+      if keys$[n]<>"" then
+         if k=i then return values$[k]
+         k++
+      endif
+   next n
+   return ""
+end function
+
+function getKeyByIndex$(i)
+   # get a key by the index
+   # remember to skip the empty keys (deleted ones)
+   k = 0
+   for n = 0 to keys$[?] -1
+      if keys$[n]<>"" then
+         if k=i then return keys$[k]
+         k++
+      endif
+   next n
+   return ""
+end function