### Number letter counts

If the numbers 1 to 5 are written out in words: one, two, three, four, five, then there are 3 + 3 + 5 + 4 + 4 = 19 letters used in total.

If all the numbers from 1 to 1000 (one thousand) inclusive were written out in words, how many letters would be used?

NOTE: Do not count spaces or hyphens. For example, 342 (three hundred and forty-two) contains 23 letters and 115 (one hundred and fifteen) contains 20 letters. The use of "and" when writing out numbers is in compliance with British usage.

Solution:

```void Solution()
{
Dictionary<int, string> numbers = new Dictionary<int, string>();
numbers.Add(1, "one");
numbers.Add(2, "two");
numbers.Add(3, "three");
numbers.Add(4, "four");
numbers.Add(5, "five");
numbers.Add(6, "six");
numbers.Add(7, "seven");
numbers.Add(8, "eight");
numbers.Add(9, "nine");
numbers.Add(10, "ten");
numbers.Add(11, "eleven");
numbers.Add(12, "twelve");
numbers.Add(13, "thirteen");
numbers.Add(14, "fourteen");
numbers.Add(15, "fifteen");
numbers.Add(16, "sixteen");
numbers.Add(17, "seventeen");
numbers.Add(18, "eighteen");
numbers.Add(19, "nineteen");
numbers.Add(20, "twenty");
numbers.Add(30, "thirty");
numbers.Add(40, "forty");
numbers.Add(50, "fifty");
numbers.Add(60, "sixty");
numbers.Add(70, "seventy");
numbers.Add(80, "eighty");
numbers.Add(90, "ninety");
numbers.Add(100, "hundred");
numbers.Add(1000, "thousand");

int sum = 0;
for (int i = 1; i <= 20; i++)
{
sum += numbers[i].Length;
Console.WriteLine(numbers[i] + " " + numbers[i].Length);
}

for (int i = 21; i < 100; i++)
{
int key = i / 10;
if (i % 10 != 0)
sum += numbers[key * 10].Length + numbers[i % 10].Length;
else
sum += numbers[key * 10].Length;
}

int sumTill1To99 = sum;

for (int i = 101; i < 999; i = i + 100)
{
int key = i / 100;
sum += numbers[key].Length + numbers.Length;
sum += (numbers[key].Length + numbers.Length + "and".Length) * 99;
sum = sum + sumTill1To99;

}

sum = sum + numbers.Length + numbers.Length;
}
```