Module vnd 

Variable Neighborhood Descent (VND) phase.

VND systematically explores multiple neighborhood structures, restarting from the first neighborhood whenever an improvement is found. This provides a structured way to combine multiple move types for better optimization.

Algorithm

1. Start with neighborhood k = 0
2. Find the best improving move in neighborhood k
3. If improvement found: apply move, restart from k = 0
4. If no improvement: move to k = k + 1
5. Terminate when k exceeds the number of neighborhoods

Zero-Erasure Design

Uses an enum-based approach where all neighborhoods generate the same move type. This allows fully monomorphized execution without trait objects in hot paths.

Structs

VndPhase

Variable Neighborhood Descent phase.