Question

For a non-negative integer X, the array-form of X is an array of its digits in left to right order. For example, if X = 1231, then the array form is [1,2,3,1].

Given the array-form A of a non-negative integer X, return the array-form of the integer X+K.

Example 1:

Input: A = [1,2,0,0], K = 34 Output: [1,2,3,4] Explanation: 1200 + 34 = 1234

Example 2:

Input: A = [2,7,4], K = 181 Output: [4,5,5] Explanation: 274 + 181 = 455

Example 3:

Input: A = [2,1,5], K = 806 Output: [1,0,2,1] Explanation: 215 + 806 = 1021

Example 4:

Input: A = [9,9,9,9,9,9,9,9,9,9], K = 1 Output: [1,0,0,0,0,0,0,0,0,0,0] Explanation: 9999999999 + 1 = 10000000000

Note：

1. 1 <= A.length <= 10000
2. 0 <= A[i] <= 9
3. 0 <= K <= 10000
4. If A.length > 1, then A[0] != 0

Difficulty:Easy

Category:

Analyze

这是123次周赛的比赛题目, 使用C++来解决这个问题的时候,显得十分笨重, 在后面的题目中,会同时考虑使用 Python 来刷Leetcode的题目.

Solution

class Solution {
 public:
  vector<int> addToArrayForm(vector<int>& A, int k) {
    // vector<int> ans;
    int n = A.size(), carry = 0;
    for (int i = n - 1; i >= 0; --i) {
      if (k > 0 || carry > 0) {
        A[i] = A[i] + k % 10 + carry;
        carry = A[i] / 10;
        A[i] = A[i] % 10;
        k = k / 10;
      }
    }
    while (k > 0 || carry > 0) {
      int temp = k % 10 + carry;
      A.insert(A.begin(), temp % 10);
      carry = temp / 10;
      k = k / 10;
    }
    return A;
  }
};

Solution 2: Python

class Solution(object):
  def addToArrayForm(self, A, K):
    v = ''.join([str(x) for x in A])
    v = int(v)
    v += K
    return [int(d) for d in str(v)]