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An inefficient version of range-merge exam
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/* | |
* Input example: 1,2,8-20,15-200 | |
* Output: 1,2,8-200 | |
*/ | |
using System; | |
using System.Collections.Generic; | |
using System.Linq; | |
namespace Fold | |
{ | |
internal class Program | |
{ | |
public static void Main(string[] args) | |
{ | |
while (true) | |
{ | |
var ranges = NormalizeRange(ReadRangeSorted()); | |
var enumerable = ranges as Tuple<int, int>[] ?? ranges.ToArray(); | |
if (!enumerable.Any()) | |
break; | |
PrintRanges(enumerable); | |
} | |
Console.WriteLine("Until next time..."); | |
} | |
private static IEnumerable<Tuple<int, int>> NormalizeRange(IEnumerable<Tuple<int, int>> ranges) | |
{ | |
var enumerable = ranges as Tuple<int, int>[] ?? ranges.ToArray(); | |
if (!enumerable.Any()) | |
return new List<Tuple<int, int>>(); | |
return enumerable.Aggregate(new [] { enumerable.First() }, | |
(prod, next) => | |
{ | |
var src = prod.Last(); | |
if (next.Item1 >= src.Item1 && next.Item1 <= src.Item2) | |
{ | |
return prod.TakeWhile((o, i) => i < prod.Length - 1).Concat( | |
new [] { Tuple.Create(src.Item1, Math.Max(src.Item2, next.Item2)) }).ToArray(); | |
} | |
return prod.Concat(new [] { next }).ToArray(); | |
} | |
); | |
} | |
private static IEnumerable<Tuple<int, int>> ReadRangeSorted() | |
{ | |
return ReadRange() | |
.Select(t => t.Item1 <= t.Item2 ? t : Tuple.Create(t.Item2, t.Item1)) | |
.OrderBy(t => t.Item1); | |
} | |
private static IEnumerable<Tuple<int, int>> ReadRange() | |
{ | |
Console.Write(">> "); | |
var line = Console.ReadLine(); | |
if (string.IsNullOrEmpty(line)) | |
return new List<Tuple<int, int>>(); | |
var ranges = line.Split(',').Select(s => s.Trim()).Where(s => !string.IsNullOrEmpty(s)) | |
.Select(s => | |
{ | |
var r = s.Split('-'); | |
if (r.Length == 2) | |
return Tuple.Create(int.Parse(r[0]), int.Parse(r[1])); | |
var val = int.Parse(r[0]); | |
return Tuple.Create(val, val); | |
}); | |
return ranges.ToList(); | |
} | |
private static void PrintRanges(IEnumerable<Tuple<int, int>> ranges) | |
{ | |
var sranges = ranges.Select(range => range.Item1 == range.Item2 | |
? Convert.ToString(range.Item1) | |
: string.Format($"{range.Item1}-{range.Item2}")); | |
Console.WriteLine(string.Join(",", sranges)); | |
} | |
} | |
} |
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