https://github.com/mikolalysenko/range-minimum-query

Preprocess an array to find the smallest element in any given interval in O(1)
https://github.com/mikolalysenko/range-minimum-query

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Preprocess an array to find the smallest element in any given interval in O(1)

• Host: GitHub
• URL: https://github.com/mikolalysenko/range-minimum-query
• Owner: mikolalysenko
• License: mit
• Created: 2014-03-28T21:04:47.000Z (over 10 years ago)
• Default Branch: master
• Last Pushed: 2014-03-29T14:22:40.000Z (over 10 years ago)
• Last Synced: 2024-10-21T01:36:19.365Z (2 months ago)
• Language: JavaScript
• Size: 137 KB
• Stars: 3
• Watchers: 4
• Forks: 1
• Open Issues: 0
• Metadata Files:
  • Readme: README.md
  • License: LICENSE

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README

        
range-minimum-query

===================

Given an array of elements, preprocess the array so that range minimum queries can be computed in constant time.

# Example

```javascript

var array = [9, 3, 7, 1, 8, 12, 10, 20, 15, 18, 5]

var rmq = require("range-minimum-query")(array)

console.log(rmq(-Infinity, Infinity), rmq(0, 3))

```

Output:

```javascript

3 1

```

# Install

```

npm install range-minimum-query

```

# API

### `var rmq = require("range-minimum-query")(array[,compare])`

Preprocess `array` for fast range minimum queries

* `array` is an array of objects

* `compare` is an optional comparison function determining an ordering on `array`

**Returns** A function `rmq` for answering range minimum queries on `array`

### `rmq(lo, hi)`

Finds the index of the smallest element in the range `[lo,hi)` in `array`

* `lo` is the start index of the bounds

* `hi` is the end index of the bounds (non-inclusive)

**Returns** The index of the smallest element in the range `[lo, hi)` in `array`

# Credits

(c) 2014 Mikola Lysenko. MIT License