class Solution: def romanToInt(self, s: str) -> int: memo={'I':1,'IV':4,'V':5,'IX':9,'X':10,'XL':40,'L':50,'XC':90,'C':100,'CD':400,'D':500,'CM':900,'M':1000} i=0 v=0 while i<len(s): if i<len(s)-1 and s[i] in ['I','X','C']: if s[i:i+2] in ['IV','IX','XL','XC','CD','CM']: v+=memo[s[i:i+2]] i+=2 else: v+=memo[s[i]] i+=1 else: v+=memo[s[i]] i+=1 return v
执行用时 :72 ms, 在所有 python3 提交中击败了65.93%的用户
内存消耗 :14.1 MB, 在所有 python3 提交中击败了5.25%的用户
——2019.10.17