Add reverse-bits solution in TS

Author: Jeehay28

reverse-bits/Jeehay28.ts

@@ -0,0 +1,70 @@
+// TC: O(1)
+// SC: O(1)
+function reverseBits(n: number): number {
+  let stack: number[] = [];
+
+  while (stack.length < 32) {
+    stack.push(n % 2);
+    n = Math.floor(n / 2);
+  }
+
+  let output: number = 0;
+  let scale: number = 1;
+
+  while (stack.length > 0) {
+    output += stack.pop()! * scale;
+    scale *= 2;
+  }
+
+  return output;
+}
+
+// TC: O(1)
+// SC: O(1)
+/*
+function reverseBits(n: number): number {
+  let result = 0;
+
+  for (let i = 0; i < 32; i++) {
+    let bit = n & 1;
+    result = (result << 1) | bit;
+    n = n >>> 1;
+  }
+
+  return result >>> 0;
+} 
+*/
+
+/*
+n & 1
+- get last bit
+- equivalent to n % 2 for non-negative integer
+
+n << 1
+- left shift (multiply by 2)
+
+n >>> 1
+- Unsigned right shift (divide by 2)
+- ignores sign
+
+n >>> 0
+- no shift, just cast to unsigned
+   
+const signed = -1;             // Binary: 11111111111111111111111111111111
+const unsigned = signed >>> 0; // 4294967295
+
+JavaScript/TypeScript only has one number type — a 64-bit float. itwise operations use 32-bit signed integers.
+    To return a 32-bit unsigned integer, use >>> 0 on the result.
+    
+    🔧 Bitwise Operations in JavaScript — Summary
+    1. Bitwise operations in JavaScript (&, |, ^, ~, <<, >>, >>>) are always performed on 32-bit signed integers.
+
+    2. Internally:
+        - JavaScript converts your number into a 32-bit signed integer
+        - Performs the bitwise operation
+        - Then converts it back into a regular 64-bit number (JavaScript's only number type)
+
+    3. If you need the result as a 32-bit unsigned integer (like for LeetCode problems dealing with uint32):
+        - Use >>> 0 at the end of your result
+        - This forces the result to be treated as an unsigned 32-bit integer
+*/