leetcode989

 class Solution:
     def addToArrayForm(self, A, K):
         i = len(A) - 1
         while i >= 0 and K > 0:
             A[i] += K
             K = A[i] // 10
             if A[i] >= 10:
                 A[i] %= 10
                 if i == 0:
                     A = [0] + A
                     i += 1
             i -= 1
         return A
         

上面这个是参考别人的解决方案，思路不好理解，我又从新写了一个啰嗦的：

 class Solution:
     def addToArrayForm(self, A: 'List[int]', K: 'int') -> 'List[int]':
         lenA = len(A)
         KS = str(K)
         lenB = len(KS)
         B = list()
         maxlen = 0
         if lenA > lenB:
             maxlen = lenA
             dis = lenA - lenB
             for i in range(dis):
                 B.append(0)
         elif lenA < lenB:
             maxlen = lenB
             dis = lenB - lenA
             for i in range(dis):
                 A.insert(0,0)
         else:
             maxlen = lenA

         for i in range(lenB):
             B.append(int(KS[i]))

         I = 0
         R = list()
         maxpotion = maxlen - 1
         while maxpotion >= 0:
             C = A[maxpotion] + B[maxpotion] + I
             if C >= 10:
                 I = 1
                 C = C % 10
             else:
                 I = 0
             R.insert(0,C)
             maxpotion -= 1

         if I == 1:
             R.insert(0,1)
         return R