每日一道算法题之LeetCode13

 1 class Solution:
 2     def romanToInt(self, s: str) -> int:
 3         dict = {‘I‘:1,‘V‘:5, ‘X‘:10, ‘L‘:50, ‘C‘:100, ‘D‘:500, ‘M‘:1000}
 4         n= len(s)
 5         sum = 0
 6         for i in range(n-1):
 7             if dict[s[i]] < dict[s[i+1]]:
 8                 sum -= dict[s[i]]
 9             else:
10                 sum += dict[s[i]]
11         return sum + dict[s[-1]]