Branchless Bit Toggle | Dataford Interview Questions

A Publicis Sapient digital experience component stores binary configuration flags as an integer. Toggle every bit within a specified width: each 0 must become 1, and each 1 must become 0.

Implement the operation without using if, else, switch, conditional expressions, or lookup tables. Bits outside the specified width must not affect the result.

Formal Specification

Implement toggle_bits(value, width):

value: a non-negative integer whose relevant binary representation uses at most width bits.
width: a positive integer representing how many least-significant bits to toggle.
Return the integer produced after toggling all width relevant bits.

Use bitwise operations. The result must contain exactly the complemented values of the selected bits, including leading zero bits within the requested width.

Constraints

0 <= value < 2 ** width
1 <= width <= 31
Only the lowest width bits are toggled
Conditional statements, switch-case statements, conditional expressions, and lookup tables are not allowed

Function Signature

def toggle_bits(value, width):

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