# euler / go / src / euler / 17.go

 ``` 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77``` ```/* 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. Answer: 21124 */ package main import "fmt" var numbers = map[int]string{ 1: "one", 2: "two", 3: "three", 4: "four", 5: "five", 6: "six", 7: "seven", 8: "eight", 9: "nine", 10: "ten", 11: "eleven", 12: "twleve", 13: "thirteen", 14: "fourteen", 15: "fifteen", 16: "sixteen", 17: "seventeen", 18: "eighteen", 19: "nineteen", 20: "twenty", 30: "thirty", 40: "forty", 50: "fifty", 60: "sixty", 70: "seventy", 80: "eighty", 90: "ninety", } func english(n int) string { if n >= 100 { hundreds := numbers[n/100] + "hundred" tens := english(n - n/100*100) if len(tens) > 0 { return hundreds + "and" + tens } else { return hundreds } } if value, ok := numbers[n]; ok { return value } if n >= 20 { return numbers[n/10*10] + numbers[n-n/10*10] } return "" } func main() { s := "onethousand" for n := 1; n < 1000; n++ { s += english(n) } fmt.Println(len(s)) } ```