From 49e73d89e6646d8aaef555a6a33ffd706e5fbf4f Mon Sep 17 00:00:00 2001
From: Matej Focko <me@mfocko.xyz>
Date: Sat, 19 Oct 2024 11:36:12 +0200
Subject: [PATCH] =?UTF-8?q?cs:=20add=20=C2=AB1545.=20Find=20the=20Kth=20Bi?=
 =?UTF-8?q?t=20in=20Nth=20Binary=20String=C2=BB?=
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URL:	https://leetcode.com/problems/find-kth-bit-in-nth-binary-string/
Signed-off-by: Matej Focko <me@mfocko.xyz>
---
 cs/find-kth-bit-in-nth-binary-string.cs | 23 +++++++++++++++++++++++
 1 file changed, 23 insertions(+)
 create mode 100644 cs/find-kth-bit-in-nth-binary-string.cs

diff --git a/cs/find-kth-bit-in-nth-binary-string.cs b/cs/find-kth-bit-in-nth-binary-string.cs
new file mode 100644
index 0000000..0e24100
--- /dev/null
+++ b/cs/find-kth-bit-in-nth-binary-string.cs
@@ -0,0 +1,23 @@
+public class Solution {
+    public char FindKthBit(int n, int k) {
+        static char GetBit(int inversions)
+            => inversions % 2 == 0 ? '1' : '0';
+
+        var length = (1 << n) - 1;
+
+        int inversions;
+        for (inversions = 0; k > 1; length >>= 1) {
+            // check for middle
+            if (k - 1 == length >> 1) {
+                return GetBit(inversions);
+            }
+
+            if (k > length >> 1) {
+                k = length + 1 - k;
+                ++inversions;
+            }
+        }
+
+        return GetBit(++inversions);
+    }
+}