reverse-bits

Author: taewanseoul

reverse-bits/taewanseoul.ts

@@ -0,0 +1,26 @@
+/**
+ * 190. Reverse Bits
+ * Reverse bits of a given 32 bits unsigned integer.
+ *
+ * https://leetcode.com/problems/reverse-bits/description/
+ */
+
+// O(1) time
+// O(1) space
+function reverseBits(n: number): number {
+  const bits: number[] = [];
+
+  while (bits.length < 32) {
+    bits.push(n & 1);
+    n = n >> 1;
+  }
+
+  let result = 0;
+  let scale = 1;
+  for (let i = bits.length - 1; i >= 0; i--) {
+    result += bits[i] * scale;
+    scale *= 2;
+  }
+
+  return result;
+}