Create 1980-find-unique-binary-string.kt

kotlin/1980-find-unique-binary-string.kt

@@ -0,0 +1,20 @@
+class Solution {
+    fun findDifferentBinaryString(nums: Array<String>): String {
+        val hs = nums.toSet()
+        val n = nums.size
+        var temp = CharArray(nums.size) { '0' }
+
+
+        fun backtrack(i: Int): Boolean {
+            if(i == n) {
+                return if(!hs.contains(temp.joinToString(""))) true else false
+            }
+            if(backtrack(i+1)) return true
+            temp[i] = '1'
+            if(backtrack(i+1)) return true
+            return false
+        }
+
+        return if(backtrack(0)) temp.joinToString("") else ""
+    }
+}