这个问题的意思是leetcode 91要求编码一个字符串,给出的代码只能统计此字符串的编码总数,而不能输出具体的编码序列。因此需要对现有的代码进行修改。
首先,需要在包含DP算法的代码中添加一个新的数组,用于存储解密后的字符串结果。具体代码如下:
def numDecodings(s: str) -> int: n = len(s) if n == 0: return 0
dp = [0] * (n + 1)
dp[0] = 1
dp[1] = 1 if s[0] != "0" else 0
# add new array to store decoded string
decoded = [""] * (n + 1)
decoded[0] = ""
decoded[1] = s[0] if s[0] != "0" else ""
for i in range(2, n + 1):
if s[i - 1] != "0":
dp[i] += dp[i - 1]
decoded[i] += decoded[i - 1]
decoded[i] += chr(int(s[i-1]) + 64)
if s[i - 2] == "1" or (s[i - 2] == "2" and s[i - 1] <= "6"):
dp[i] += dp[i - 2]
decoded[i] = decoded[i][:len(decoded[i-2])] if i > 2 else decoded[i]
elif s[i-2] != "0":
decoded[i] += chr(int(s[i-2])*10 + int(s[i-1]) + 64)
if decoded[i] == "":
return 0
print(decoded[n]) # output decoded string
return dp[n]
接着,在主函数中调用numDecodings函数即可得到解密后的字符串结果:
if name == "main": s = "226" res = numDecodings(s) print(res)
此时,