每日一题---13. 罗马数字转整数[力扣][Go]

func romanToInt(s string) int {
  v := []int{1,4,5,9,10,40,50,90,100,400,500,900,1000}
  str := []string{"I", "a", "V", "b", "X", "c", "L", "d", "C", "e", "D", "f", "M"}
  s = charChange(s)
  n := len(s)
  sum :=0
  for i := 0; i < n; i++ {
    for j := 12; j >= 0; j-- {
      if string(s[i]) == str[j] {
        sum += v[j]
        break
      }
    }
  }
  return sum
}
func charChange(s string) string {
  s = strings.Replace(s,"IV","a",-1)
  s = strings.Replace(s,"IX","b",-1)
  s = strings.Replace(s,"XL","c",-1)
  s = strings.Replace(s,"XC","d",-1)
  s = strings.Replace(s,"CD","e",-1)
  s = strings.Replace(s,"CM","f",-1)
  return s
}