CPU Register Bitwise Operations
Headlands Technologies● EasyFULLTIMEPHONE SCREENProblem statement
Simulate one unsigned 32-bit register. You receive its initial nonnegative value initialValue and a sequence operations. Process the operations in order. Bit 0 is the least significant bit, and bit 31 is the most significant bit.
Each operation is a pair [opcode, bitIndex]:
0: set that bit to1.1: clear that bit to0.2: toggle that bit.3: test that bit without changing the register.
Return one integer for every operation, in the same order. After set, clear or toggle, return the entire updated register value. For test, return 0 or 1 for the requested bit. Preserve repeated operations; an empty sequence returns an empty array.
Values from 0 through 4294967295 are nonnegative register values. Use signed 64-bit storage for the input and outputs so bit 31 is preserved without making the result negative.
Function
simulateRegister(initialValue: long, operations: int[][]) → long[]Examples
Example 1
initialValue = 0operations = [[0,0],[0,3],[3,3],[1,0],[2,3],[3,3]]return = [1,9,1,8,0,0]Set bits 0 and 3 to obtain 9. Testing bit 3 returns 1 without changing the register. Clearing bit 0 leaves 8; toggling bit 3 clears it.
Example 2
initialValue = 4294967295operations = [[3,31],[1,31],[3,31],[2,0],[0,31],[3,0]]return = [1,2147483647,0,2147483646,4294967294,0]Bit 31 is a normal data bit. Clearing it leaves 2147483647. Later restoring it produces 4294967294, kept positive in signed 64-bit storage.
Example 3
initialValue = 10operations = [[3,0],[3,1],[2,0],[3,0],[0,1],[1,3],[3,3]]return = [0,1,11,1,11,3,0]The initial value 10 has bits 1 and 3 set. Test returns a bit, toggle flips only the target, and setting an already-set bit leaves the value unchanged.
Constraints
0 <= initialValue <= 4294967295.0 <= operations.length <= 100000.- Each operation contains exactly two integers:
0 <= opcode <= 3and0 <= bitIndex <= 31. - All operations are valid. No other CPU instructions or registers are simulated.