Range expansion

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Revision as of 12:45, 16 July 2010 by rosettacode>Paddy3118 (Link to separate format page)
Task
Range expansion
You are encouraged to solve this task according to the task description, using any language you may know.

Expand the range of integers -6,-3-1,3-5,7-11,14,15,17-20 which is in the format described in Range extraction/Format to a list of integers.

ALGOL 68

Works with: ALGOL 68 version Revision 1 - no extensions to language used
Works with: ALGOL 68G version Any - tested with release 1.18.0-9h.tiny
Works with: ELLA ALGOL 68 version Any (with appropriate job cards) - tested with release 1.8-8d

<lang algol68>MODE YIELDINT = PROC(INT)VOID;

MODE RANGE = STRUCT(INT lwb, upb); MODE RANGEINT = UNION(RANGE, INT);

OP SIZEOF = ([]RANGEINT list)INT: (

  1. determine the length of the output array #
 INT upb := LWB list - 1;
 FOR key FROM LWB list TO UPB list DO
   CASE list[key] IN
     (RANGE value): upb +:= upb OF value - lwb OF value + 1,
     (INT): upb +:= 1
   ESAC
 OD;
 upb

);

PROC gen range expand = ([]RANGEINT list, YIELDINT yield)VOID:

 FOR key FROM LWB list TO UPB list DO
   CASE list[key] IN
     (RANGE range): FOR value FROM lwb OF range TO upb OF range DO yield(value) OD,
     (INT int): yield(int)
   ESAC
 OD;

PROC range expand = ([]RANGEINT list)[]INT: (

  1. Finally full the output array with a generator #
 [LWB list: LWB list + SIZEOF list - 1]INT out;
 INT upb := LWB out - 1;
  1. FOR INT value IN # gen range expand(list, # ) DO #
    1. (INT value)VOID:
   out[upb +:= 1] := value
  1. OD #);
 out

);

test:(

 []RANGEINT list = (-6, RANGE(-3, 1), RANGE(3, 5),  RANGE(7, 11), 14, 15, RANGE(17, 20));
 print((range expand(list), new line))

)</lang> Output:

         -6         -3         -2         -1         +0         +1         +3         +4         +5         +7         +8         +9        +10        +11        +14        +15        +17        +18        +19        +20

Python

<lang python>def rangeexpand(txt):

   lst = []
   for r in txt.split(','):
       if '-' in r[1:]:
           r0, r1 = r[1:].split('-', 1)
           lst += range(int(r[0] + r0), int(r1) + 1)
       else:
           lst.append(int(r))
   return lst

print(rangeexpand('-6,-3-1,3-5,7-11,14,15,17-20'))</lang>

Sample output

[-6, -3, -2, -1, 0, 1, 3, 4, 5, 7, 8, 9, 10, 11, 14, 15, 17, 18, 19, 20]