Add solution #967

Author: JoshCrozier

README.md

@@ -1,4 +1,4 @@
-# 1,051 LeetCode solutions in JavaScript
+# 1,052 LeetCode solutions in JavaScript
 
 [https://leetcode.com/](https://leetcode.com/)
 
@@ -775,6 +775,7 @@
 964|[Least Operators to Express Number](./solutions/0964-least-operators-to-express-number.js)|Hard|
 965|[Univalued Binary Tree](./solutions/0965-univalued-binary-tree.js)|Easy|
 966|[Vowel Spellchecker](./solutions/0966-vowel-spellchecker.js)|Medium|
+967|[Numbers With Same Consecutive Differences](./solutions/0967-numbers-with-same-consecutive-differences.js)|Medium|
 970|[Powerful Integers](./solutions/0970-powerful-integers.js)|Easy|
 976|[Largest Perimeter Triangle](./solutions/0976-largest-perimeter-triangle.js)|Easy|
 977|[Squares of a Sorted Array](./solutions/0977-squares-of-a-sorted-array.js)|Easy|

solutions/0967-numbers-with-same-consecutive-differences.js

@@ -0,0 +1,42 @@
+/**
+ * 967. Numbers With Same Consecutive Differences
+ * https://leetcode.com/problems/numbers-with-same-consecutive-differences/
+ * Difficulty: Medium
+ *
+ * Given two integers n and k, return an array of all the integers of length n where the difference
+ * between every two consecutive digits is k. You may return the answer in any order.
+ *
+ * Note that the integers should not have leading zeros. Integers as 02 and 043 are not allowed.
+ */
+
+/**
+ * @param {number} n
+ * @param {number} k
+ * @return {number[]}
+ */
+var numsSameConsecDiff = function(n, k) {
+  const result = [];
+
+  for (let digit = 1; digit <= 9; digit++) {
+    buildNumber(digit, n - 1);
+  }
+
+  return result;
+
+  function buildNumber(current, digitsLeft) {
+    if (digitsLeft === 0) {
+      result.push(current);
+      return;
+    }
+
+    const lastDigit = current % 10;
+
+    if (lastDigit + k <= 9) {
+      buildNumber(current * 10 + lastDigit + k, digitsLeft - 1);
+    }
+
+    if (k !== 0 && lastDigit - k >= 0) {
+      buildNumber(current * 10 + lastDigit - k, digitsLeft - 1);
+    }
+  }
+};