# Add to Array-Form of Integer Leetcode

## Add to Array-Form of Integer Solution

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

Constraint:

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

### SOLUTION

Program: Add to Array-Form of Integer Solution in Java

``````auto speedup = []() {
ios::sync_with_stdio(false);
cin.tie(nullptr);
cout.tie(nullptr);
return nullptr;
}();

class Solution {
public:
vector<int> addToArrayForm(vector<int>& A, int K) {
vector<int> ans;
int j = A.size() - 1, carry = 0;
while (K > 0 && j >= 0) {
int curr = A[j--] + carry + K % 10;
ans.push_back(curr % 10);
carry = curr / 10;
K /= 10;
}
while (j >= 0) {
int curr = A[j--] + carry;
ans.push_back(curr % 10);
carry = curr / 10;
}
while (K > 0) {
int curr = K % 10 + carry;
ans.push_back(curr % 10);
carry = curr / 10;
K /= 10;
}
if (carry > 0) ans.push_back(carry);
reverse(ans.begin(), ans.end());
return ans;
}
};``````