Algorithms

_Algorithms_

1

heap-min.js

// node -i -e "var heap = require('./heap-min').heap()"

exports.heap = function() {
  var items = [];

  var root = function() {
    return items[0];
  };

  var addNode = function(e) {
    return items.push(e);
  }

  return {
    root: root,
    addNode: addNode
  }
}

quickSort.js

// pick a pivot (last element)
// draw a wall, lowest index
// left most element (current element)

// iterate and put all elements smaller than the pivot
// to the left of the wall
//
// and all elements larger than the pivot to the right of the wall
//
// then drop the pivot in between the wall, so that
// all numbers larger than it and smaller than it are in the
// right half
//
// to swap, if the element is less than the pivot,
// switch the element next to the wall then increment
// wall

function quickSort(list, left, right) {
  if (typeof left === 'undefined') left = 0;
  if (typeof right === 'undefined') right = list.length - 1;
  if (left >= right) return list;

  var current = left;
  var wall = left;

  for(current; current < right ; current++) {
    if (list[current] <= list[right]) {
      swap(list, current, wall);
      wall++;
    }
  }

  swap(list, wall, right)

  quickSort(list, left, wall - 1);
  quickSort(list, wall, right);

  return list;
}

function swap(list, indexA, indexB) {
  var temp = list[indexA]
  list[indexA] = list[indexB];
  list[indexB] = temp;
}

const arguments =  process.argv.slice(2).map(function (e){
  return parseInt(e, 10);
})

const res = quickSort(arguments);

console.log(res);