Data update

Task/Roman-numerals-Decode/PascalABC.NET/roman-numerals-decode-1.pas

@@ -1,39 +1,20 @@
-function Rim2Arab(S : String) : Integer;
-const //римские числа на соответствующие десятичные числа
-R : array[1..14] of String[2] = ('M','CM','D','CD','C','XC','L','XL','X','IX','V','IV','I',' ');
-A : array[1..14] of Integer = (1000, 900, 500, 400, 100, 90, 50, 40, 10, 9, 5, 4, 1, 0);
+function romanDecode(roman: string): integer;
 begin
-  var i := 1;
+  var values := Dict('I' to 1, 'V' to 5, 'X' to 10, 'L' to 50, 'C' to 100, 'D' to 500, 'M' to 1000);
   Result := 0;
-  while S.Length > 0 do
-    begin
-      while S.IndexOf(R[i]) = 0 do
-        begin
-          S := S.Remove(0, R[i].Length);
-          Result += A[i]
-        end;
-      i += 1;
-    end;
+  var prev := 0;
+  for var i := roman.Length downto 1 do
+  begin
+    var curr := values[roman[i]];
+    if curr < prev
+    then Result -= curr
+    else Result += curr;
+    prev := curr;
+  end;
 end;
-
-const
-   L = 'IVXLCDM';
 begin
-  var S := 'MDCLXVI';//'roman numeral:';
-  Write(S,': ');
-  var index := 1;
-  repeat
-    if L.IndexOf(S[index]) < 0 then
-      index += 1
-    else
-      begin
-        var Rim : String := '';
-        repeat
-          Rim += S[index];
-          S := S.Remove(index - 1, 1);
-        until (S.Length < index) or (L.IndexOf(S[index]) < 0);
-        S := S.Insert(index - 1, Rim2Arab(Rim).ToString);
-      end;
-  until index > S.Length;
-  WriteLn(S);
+  var romans := |'I', 'III', 'IV', 'VIII', 'XLIX', 'CCII',
+                 'CDXXXIII', 'MCMXC', 'MMVIII', 'MDCLXVI'|;
+  foreach var roman in romans do
+    writeln(roman:8, romanDecode(roman):7);
 end.