# Crate skipping_search[−][src]

skipping-search is a fast iterator variant for intersection computations.

# Examples

Let's say you want to find the least common multiple of 4 different numbers and you've forgotten efficent ways of generating it. You can collect large arrays of the multiples of each, then use this crate to intersect them efficiently.

use skipping_search::{SkippingIterator, MultiIntersection, CountingIntersection}; let multiples = vec![12, 16, 22, 35].into_iter().map(|n|{ (1..).map(|i|{i * n}).take_while(|p|{p < &100_000}).collect::<Vec<_>>() }).collect::<Vec<_>>(); let mut common_multiples = SkippingIterator::new( MultiIntersection::new( // Collect each vector as a slice. multiples.iter().map(Vec::as_slice).collect(), ), ); assert_eq!(common_multiples.cloned().next(), Some(18480));

Now that we've paid the cost of generating this data, we can make other combining queries very cheaply:

let mut subcommon_multiples = SkippingIterator::new( CountingIntersection::new( // Collect each vector as a slice. multiples.iter().map(Vec::as_slice).collect(), // We want any multiple common to at least 3 of the numbers 3, ), ); assert_eq!( subcommon_multiples.cloned().take(10).collect::<Vec<_>>(), vec![528, 1056, 1584, 1680, 2112, 2640, 3168, 3360, 3696, 4224], );

## Structs

CountingIntersection |
Combines an arbitrary number of |

MultiIntersection |
Combines an arbitrary number of |

PairIntersection |
Combines two |

SkippingIterator |
Turns a |

## Traits

SkippingSearch |
A trait used to implement inverted-index-style fast intersection. It differs from Iterator in two main ways: |