13. 罗马数字转整数

package main
import "fmt"
func romanToInt(s string) int {
   m :=map[string]int{"I":1,"V":5,"X":10,"L":50,"C":100,"D":500,"M":1000}
   temp :=0
   var result int
   for i:=len(s)-1;i>=0;i--{
          num := m[string(s[i])]
       //'IV' 4
       if num<temp&&(num==1||num==10||num==100) {
           result -=num
       }else {
              result +=num
       }
       temp = num
   }
   return result
}
func main() {
    fmt.Println(romanToInt("IV"))
    fmt.Println(romanToInt("MCMXCIV"))
}