Function optimize 

pub fn optimize(
    sampler: &dyn Sampler,
    problem: &Problem,
    seed: u64,
    budget: usize,
) -> Result<Curve>

Runs sampler on problem for budget trials and returns the best-value curve.

The sequential oracle: each trial is completed and folded into the history before the next is asked, so the sampler always sees the full record of what came before — which is the standard, single-worker benchmark protocol. The returned Curve has one entry per trial: the best objective seen so far.

Errors

As suggest, plus Error::InvalidSpace if the problem’s schema is malformed (the built-in problems never are).