<p>Given two integers n and k, return <em>an array of all the integers of length </em><code>n</code><em> where the difference between every two consecutive digits is </em><code>k</code>. You may return the answer in <strong>any order</strong>.</p>

<p>Note that the integers should not have leading zeros. Integers as <code>02</code> and <code>043</code> are not allowed.</p>

<p>&nbsp;</p>
<p><strong class="example">Example 1:</strong></p>

<pre>
<strong>Input:</strong> n = 3, k = 7
<strong>Output:</strong> [181,292,707,818,929]
<strong>Explanation:</strong> Note that 070 is not a valid number, because it has leading zeroes.
</pre>

<p><strong class="example">Example 2:</strong></p>

<pre>
<strong>Input:</strong> n = 2, k = 1
<strong>Output:</strong> [10,12,21,23,32,34,43,45,54,56,65,67,76,78,87,89,98]
</pre>

<p>&nbsp;</p>
<p><strong>Constraints:</strong></p>

<ul>
	<li><code>2 &lt;= n &lt;= 9</code></li>
	<li><code>0 &lt;= k &lt;= 9</code></li>
</ul>

class Solution {
public:
    vector<int> numsSameConsecDiff(int n, int k) {
        vector<int> prev = {1, 2, 3, 4, 5, 6, 7, 8, 9};
        for (int i = 1; i < n; ++i) {
            vector<int> curr;
            for (int j : prev) {
                int lastDigit = j % 10;
                if (lastDigit - k >= 0) {
                    curr.push_back(j * 10 + (lastDigit - k));
                }

                if (k != 0 && lastDigit + k < 10) {
                    curr.push_back(j*10 + (lastDigit + k));
                }
            }
            swap(prev, curr);
        }
        return prev;
    }
};
8700