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class Program { static void Main(string[] args) { PrintOddNumbersBetween(1, 99); Console.ReadKey(); } private static void PrintOddNumbersBetween(int startNumber, int endNumber) { var oddNumbersList = string.Join(",", OddNumbers.Range(startNumber, endNumber)); Console.WriteLine(oddNumbersList); } } static class OddNumbers { public static IEnumerable<int> Range(int startValue, int endValue) { if (startValue > endValue) { throw new ArgumentOutOfRangeException("endValue", "endValue must be greater than startValue"); } for (var currentValue = startValue; currentValue <= endValue; ++currentValue) { if (IsOddNumber(currentValue)) { yield return currentValue; } } } private static bool IsOddNumber(int value) { return (value % 2) != 0; } }

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