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// Roman Numerals, stollen from http://rosettacode.org/wiki/Roman_numerals/Encode#Go

package main

var (
	m0 = []string{"", "I", "II", "III", "IV", "V", "VI", "VII", "VIII", "IX"}
	m1 = []string{"", "X", "XX", "XXX", "XL", "L", "LX", "LXX", "LXXX", "XC"}
	m2 = []string{"", "C", "CC", "CCC", "CD", "D", "DC", "DCC", "DCCC", "CM"}
	m3 = []string{"", "M", "MM", "MMM", "I̅V̅", "V̅", "V̅I̅", "V̅I̅I̅", "V̅I̅I̅I̅", "I̅X̅"}
	m4 = []string{"", "X̅", "X̅X̅", "X̅X̅X̅", "X̅L̅", "L̅", "L̅X̅", "L̅X̅X̅", "L̅X̅X̅X̅", "X̅C̅"}
	m5 = []string{"", "C̅", "C̅C̅", "C̅C̅C̅", "C̅D̅", "D̅", "D̅C̅", "D̅C̅C̅", "D̅C̅C̅C̅", "C̅M̅"}
	m6 = []string{"", "M̅", "M̅M̅", "M̅M̅M̅"}
)

func formatRoman(n int) string {
	switch {
	case n == 0:
		return "N"
	case n < 0 || n >= 4e6:
		return "N̅"
	default:
		return m6[n/1e6] + m5[n%1e6/1e5] + m4[n%1e5/1e4] +
			m3[n%1e4/1e3] + m2[n%1e3/1e2] + m1[n%100/10] + m0[n%10]
	}
}