题解 | #把数字翻译成字符串#

思路：动态规划，dp的i + 1位存储nums的i字符可翻译成字符串的个数

1、如果当前位可以翻译成1-9（a-i），dp[i+1] += dp[i] 2、如果当前位位10-26的个位（j-z），dp[i+1] += dp[i-1]

class Solution:
    def solve(self , nums: str) -> int:
        # write code here
        
        if len(nums) == 0:
            return 0
        
        dp = [0] * (len(nums) + 1)
        dp[0] = 1
        
        for i in range(len(nums)):
            
            if nums[i] != '0':
                dp[i+1] += dp[i]
                
            if i > 0 and nums[i-1] != '0' and int(nums[i-1:i+1]) <= 26:
                dp[i+1] += dp[i-1]
        return dp[-1]