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); + } +}