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CMP.5:4.4 - Construct an admissible original candidate

Give an effective recovery operation when a candidate is needed. Rounding, selecting a subset, scheduling fractional allocations, repairing violated conditions or searching near the relaxed answer can serve this role. Test the original conditions after recovery and explain why the operation preserves or restores them.

A generic instruction to “round the result” is insufficient. Rounding upward can violate a capacity limit, while rounding downward can leave coverage incomplete. Derive the direction and any subsequent repair from the constraints.

Track objective change through recovery. If every recovered candidate has cost at most α times an attained minimizing relaxation value R*, then C≤α*R*≤α*original optimum for nonnegative costs and the stated approximation factor. If the relaxed solver returns only a feasible value P, the first inequality may still hold with P, but the comparison to the original optimum needs a separate bound on P or a direct comparison of C with a justified lower bound.

Recovery can fail or produce no better candidate. Retain an already admissible better candidate. A useful bound alone can still guide search or show that further improvement is too small to matter.