Create 1545-find-kth-bit-in-nth-binary-string.js

Author: everthis

1545-find-kth-bit-in-nth-binary-string.js

@@ -0,0 +1,17 @@
+/**
+ * @param {number} n
+ * @param {number} k
+ * @return {character}
+ */
+var findKthBit = function(n, k) {
+  let count = 0, l = (1 << n) - 1;
+  while (k > 1) {
+    if (k == Math.floor(l / 2) + 1) return count % 2 == 0 ? '1' : '0';
+    if (k > l / 2) {
+      k = l + 1 - k;
+      count++;
+    }
+    l = Math.floor(l / 2);
+  }
+  return count % 2 === 0 ? '0' : '1'; 
+};