Add solution #1980

Author: JoshCrozier

README.md

@@ -531,6 +531,7 @@
 1926|[Nearest Exit from Entrance in Maze](./1926-nearest-exit-from-entrance-in-maze.js)|Medium|
 1929|[Concatenation of Array](./1929-concatenation-of-array.js)|Easy|
 1935|[Maximum Number of Words You Can Type](./1935-maximum-number-of-words-you-can-type.js)|Easy|
+1980|[Find Unique Binary String](./1980-find-unique-binary-string.js)|Medium|
 1985|[Find the Kth Largest Integer in the Array](./1985-find-the-kth-largest-integer-in-the-array.js)|Medium|
 1996|[The Number of Weak Characters in the Game](./1996-the-number-of-weak-characters-in-the-game.js)|Medium|
 2000|[Reverse Prefix of Word](./2000-reverse-prefix-of-word.js)|Easy|

solutions/1980-find-unique-binary-string.js

@@ -0,0 +1,17 @@
+/**
+ * 1980. Find Unique Binary String
+ * https://leetcode.com/problems/find-unique-binary-string/
+ * Difficulty: Medium
+ *
+ * Given an array of strings nums containing n unique binary strings each of length n,
+ * return a binary string of length n that does not appear in nums. If there are multiple
+ * answers, you may return any of them.
+ */
+
+/**
+ * @param {string[]} nums
+ * @return {string}
+ */
+var findDifferentBinaryString = function(nums) {
+  return nums.map((n, i) => n[i] === '0' ? '1' : '0').join('');
+};