FM / functional-red-black-tree

/var/www/qr4y.gr/server/delivery/node_modules/functional-red-black-tree/

/var/www/qr4y.gr/server/delivery/node_modules/functional-red-black-tree

Name	Size	Mode	Actions
bench/	-	0755	rm
test/	-	0755	rm
.npmignore	109	0644	edit dl rm
LICENSE	1082	0644	edit dl rm
package.json	800	0644	edit dl rm
rbtree.js	22324	0644	edit dl rm
README.md	7159	0644	edit dl rm

Edit: /var/www/qr4y.gr/server/delivery/node_modules/functional-red-black-tree/rbtree.js (22324B)

"use strict"

module.exports = createRBTree

var RED   = 0
var BLACK = 1

function RBNode(color, key, value, left, right, count) {
  this._color = color
  this.key = key
  this.value = value
  this.left = left
  this.right = right
  this._count = count
}

function cloneNode(node) {
  return new RBNode(node._color, node.key, node.value, node.left, node.right, node._count)
}

function repaint(color, node) {
  return new RBNode(color, node.key, node.value, node.left, node.right, node._count)
}

function recount(node) {
  node._count = 1 + (node.left ? node.left._count : 0) + (node.right ? node.right._count : 0)
}

function RedBlackTree(compare, root) {
  this._compare = compare
  this.root = root
}

var proto = RedBlackTree.prototype

Object.defineProperty(proto, "keys", {
  get: function() {
    var result = []
    this.forEach(function(k,v) {
      result.push(k)
    })
    return result
  }
})

Object.defineProperty(proto, "values", {
  get: function() {
    var result = []
    this.forEach(function(k,v) {
      result.push(v)
    })
    return result
  }
})

//Returns the number of nodes in the tree
Object.defineProperty(proto, "length", {
  get: function() {
    if(this.root) {
      return this.root._count
    }
    return 0
  }
})

//Insert a new item into the tree
proto.insert = function(key, value) {
  var cmp = this._compare
  //Find point to insert new node at
  var n = this.root
  var n_stack = []
  var d_stack = []
  while(n) {
    var d = cmp(key, n.key)
    n_stack.push(n)
    d_stack.push(d)
    if(d <= 0) {
      n = n.left
    } else {
      n = n.right
    }
  }
  //Rebuild path to leaf node
  n_stack.push(new RBNode(RED, key, value, null, null, 1))
  for(var s=n_stack.length-2; s>=0; --s) {
    var n = n_stack[s]
    if(d_stack[s] <= 0) {
      n_stack[s] = new RBNode(n._color, n.key, n.value, n_stack[s+1], n.right, n._count+1)
    } else {
      n_stack[s] = new RBNode(n._color, n.key, n.value, n.left, n_stack[s+1], n._count+1)
    }
  }
  //Rebalance tree using rotations
  //console.log("start insert", key, d_stack)
  for(var s=n_stack.length-1; s>1; --s) {
    var p = n_stack[s-1]
    var n = n_stack[s]
    if(p._color === BLACK || n._color === BLACK) {
      break
    }
    var pp = n_stack[s-2]
    if(pp.left === p) {
      if(p.left === n) {
        var y = pp.right
        if(y && y._color === RED) {
          //console.log("LLr")
          p._color = BLACK
          pp.right = repaint(BLACK, y)
          pp._color = RED
          s -= 1
        } else {
          //console.log("LLb")
          pp._color = RED
          pp.left = p.right
          p._color = BLACK
          p.right = pp
          n_stack[s-2] = p
          n_stack[s-1] = n
          recount(pp)
          recount(p)
          if(s >= 3) {
            var ppp = n_stack[s-3]
            if(ppp.left === pp) {
              ppp.left = p
            } else {
              ppp.right = p
            }
          }
          break
        }
      } else {
        var y = pp.right
        if(y && y._color === RED) {
          //console.log("LRr")
          p._color = BLACK
          pp.right = repaint(BLACK, y)
          pp._color = RED
          s -= 1
        } else {
          //console.log("LRb")
          p.right = n.left
          pp._color = RED
          pp.left = n.right
          n._color = BLACK
          n.left = p
          n.right = pp
          n_stack[s-2] = n
          n_stack[s-1] = p
          recount(pp)
          recount(p)
          recount(n)
          if(s >= 3) {
            var ppp = n_stack[s-3]
            if(ppp.left === pp) {
              ppp.left = n
            } else {
              ppp.right = n
            }
          }
          break
        }
      }
    } else {
      if(p.right === n) {
        var y = pp.left
        if(y && y._color === RED) {
          //console.log("RRr", y.key)
          p._color = BLACK
          pp.left = repaint(BLACK, y)
          pp._color = RED
          s -= 1
        } else {
          //console.log("RRb")
          pp._color = RED
          pp.right = p.left
          p._color = BLACK
          p.left = pp
          n_stack[s-2] = p
          n_stack[s-1] = n
          recount(pp)
          recount(p)
          if(s >= 3) {
            var ppp = n_stack[s-3]
            if(ppp.right === pp) {
              ppp.right = p
            } else {
              ppp.left = p
            }
          }
          break
        }
      } else {
        var y = pp.left
        if(y && y._color === RED) {
          //console.log("RLr")
          p._color = BLACK
          pp.left = repaint(BLACK, y)
          pp._color = RED
          s -= 1
        } else {
          //console.log("RLb")
          p.left = n.right
          pp._color = RED
          pp.right = n.left
          n._color = BLACK
          n.right = p
          n.left = pp
          n_stack[s-2] = n
          n_stack[s-1] = p
          recount(pp)
          recount(p)
          recount(n)
          if(s >= 3) {
            var ppp = n_stack[s-3]
            if(ppp.right === pp) {
              ppp.right = n
            } else {
              ppp.left = n
            }
          }
          break
        }
      }
    }
  }
  //Return new tree
  n_stack[0]._color = BLACK
  return new RedBlackTree(cmp, n_stack[0])
}

//Visit all nodes inorder
function doVisitFull(visit, node) {
  if(node.left) {
    var v = doVisitFull(visit, node.left)
    if(v) { return v }
  }
  var v = visit(node.key, node.value)
  if(v) { return v }
  if(node.right) {
    return doVisitFull(visit, node.right)
  }
}

//Visit half nodes in order
function doVisitHalf(lo, compare, visit, node) {
  var l = compare(lo, node.key)
  if(l <= 0) {
    if(node.left) {
      var v = doVisitHalf(lo, compare, visit, node.left)
      if(v) { return v }
    }
    var v = visit(node.key, node.value)
    if(v) { return v }
  }
  if(node.right) {
    return doVisitHalf(lo, compare, visit, node.right)
  }
}

//Visit all nodes within a range
function doVisit(lo, hi, compare, visit, node) {
  var l = compare(lo, node.key)
  var h = compare(hi, node.key)
  var v
  if(l <= 0) {
    if(node.left) {
      v = doVisit(lo, hi, compare, visit, node.left)
      if(v) { return v }
    }
    if(h > 0) {
      v = visit(node.key, node.value)
      if(v) { return v }
    }
  }
  if(h > 0 && node.right) {
    return doVisit(lo, hi, compare, visit, node.right)
  }
}

proto.forEach = function rbTreeForEach(visit, lo, hi) {
  if(!this.root) {
    return
  }
  switch(arguments.length) {
    case 1:
      return doVisitFull(visit, this.root)
    break

case 2:
      return doVisitHalf(lo, this._compare, visit, this.root)
    break

case 3:
      if(this._compare(lo, hi) >= 0) {
        return
      }
      return doVisit(lo, hi, this._compare, visit, this.root)
    break
  }
}

//First item in list
Object.defineProperty(proto, "begin", {
  get: function() {
    var stack = []
    var n = this.root
    while(n) {
      stack.push(n)
      n = n.left
    }
    return new RedBlackTreeIterator(this, stack)
  }
})

//Last item in list
Object.defineProperty(proto, "end", {
  get: function() {
    var stack = []
    var n = this.root
    while(n) {
      stack.push(n)
      n = n.right
    }
    return new RedBlackTreeIterator(this, stack)
  }
})

//Find the ith item in the tree
proto.at = function(idx) {
  if(idx < 0) {
    return new RedBlackTreeIterator(this, [])
  }
  var n = this.root
  var stack = []
  while(true) {
    stack.push(n)
    if(n.left) {
      if(idx < n.left._count) {
        n = n.left
        continue
      }
      idx -= n.left._count
    }
    if(!idx) {
      return new RedBlackTreeIterator(this, stack)
    }
    idx -= 1
    if(n.right) {
      if(idx >= n.right._count) {
        break
      }
      n = n.right
    } else {
      break
    }
  }
  return new RedBlackTreeIterator(this, [])
}

proto.ge = function(key) {
  var cmp = this._compare
  var n = this.root
  var stack = []
  var last_ptr = 0
  while(n) {
    var d = cmp(key, n.key)
    stack.push(n)
    if(d <= 0) {
      last_ptr = stack.length
    }
    if(d <= 0) {
      n = n.left
    } else {
      n = n.right
    }
  }
  stack.length = last_ptr
  return new RedBlackTreeIterator(this, stack)
}

proto.gt = function(key) {
  var cmp = this._compare
  var n = this.root
  var stack = []
  var last_ptr = 0
  while(n) {
    var d = cmp(key, n.key)
    stack.push(n)
    if(d < 0) {
      last_ptr = stack.length
    }
    if(d < 0) {
      n = n.left
    } else {
      n = n.right
    }
  }
  stack.length = last_ptr
  return new RedBlackTreeIterator(this, stack)
}

proto.lt = function(key) {
  var cmp = this._compare
  var n = this.root
  var stack = []
  var last_ptr = 0
  while(n) {
    var d = cmp(key, n.key)
    stack.push(n)
    if(d > 0) {
      last_ptr = stack.length
    }
    if(d <= 0) {
      n = n.left
    } else {
      n = n.right
    }
  }
  stack.length = last_ptr
  return new RedBlackTreeIterator(this, stack)
}

proto.le = function(key) {
  var cmp = this._compare
  var n = this.root
  var stack = []
  var last_ptr = 0
  while(n) {
    var d = cmp(key, n.key)
    stack.push(n)
    if(d >= 0) {
      last_ptr = stack.length
    }
    if(d < 0) {
      n = n.left
    } else {
      n = n.right
    }
  }
  stack.length = last_ptr
  return new RedBlackTreeIterator(this, stack)
}

//Finds the item with key if it exists
proto.find = function(key) {
  var cmp = this._compare
  var n = this.root
  var stack = []
  while(n) {
    var d = cmp(key, n.key)
    stack.push(n)
    if(d === 0) {
      return new RedBlackTreeIterator(this, stack)
    }
    if(d <= 0) {
      n = n.left
    } else {
      n = n.right
    }
  }
  return new RedBlackTreeIterator(this, [])
}

//Removes item with key from tree
proto.remove = function(key) {
  var iter = this.find(key)
  if(iter) {
    return iter.remove()
  }
  return this
}

//Returns the item at `key`
proto.get = function(key) {
  var cmp = this._compare
  var n = this.root
  while(n) {
    var d = cmp(key, n.key)
    if(d === 0) {
      return n.value
    }
    if(d <= 0) {
      n = n.left
    } else {
      n = n.right
    }
  }
  return
}

//Iterator for red black tree
function RedBlackTreeIterator(tree, stack) {
  this.tree = tree
  this._stack = stack
}

var iproto = RedBlackTreeIterator.prototype

//Test if iterator is valid
Object.defineProperty(iproto, "valid", {
  get: function() {
    return this._stack.length > 0
  }
})

//Node of the iterator
Object.defineProperty(iproto, "node", {
  get: function() {
    if(this._stack.length > 0) {
      return this._stack[this._stack.length-1]
    }
    return null
  },
  enumerable: true
})

//Makes a copy of an iterator
iproto.clone = function() {
  return new RedBlackTreeIterator(this.tree, this._stack.slice())
}

//Swaps two nodes
function swapNode(n, v) {
  n.key = v.key
  n.value = v.value
  n.left = v.left
  n.right = v.right
  n._color = v._color
  n._count = v._count
}

//Fix up a double black node in a tree
function fixDoubleBlack(stack) {
  var n, p, s, z
  for(var i=stack.length-1; i>=0; --i) {
    n = stack[i]
    if(i === 0) {
      n._color = BLACK
      return
    }
    //console.log("visit node:", n.key, i, stack[i].key, stack[i-1].key)
    p = stack[i-1]
    if(p.left === n) {
      //console.log("left child")
      s = p.right
      if(s.right && s.right._color === RED) {
        //console.log("case 1: right sibling child red")
        s = p.right = cloneNode(s)
        z = s.right = cloneNode(s.right)
        p.right = s.left
        s.left = p
        s.right = z
        s._color = p._color
        n._color = BLACK
        p._color = BLACK
        z._color = BLACK
        recount(p)
        recount(s)
        if(i > 1) {
          var pp = stack[i-2]
          if(pp.left === p) {
            pp.left = s
          } else {
            pp.right = s
          }
        }
        stack[i-1] = s
        return
      } else if(s.left && s.left._color === RED) {
        //console.log("case 1: left sibling child red")
        s = p.right = cloneNode(s)
        z = s.left = cloneNode(s.left)
        p.right = z.left
        s.left = z.right
        z.left = p
        z.right = s
        z._color = p._color
        p._color = BLACK
        s._color = BLACK
        n._color = BLACK
        recount(p)
        recount(s)
        recount(z)
        if(i > 1) {
          var pp = stack[i-2]
          if(pp.left === p) {
            pp.left = z
          } else {
            pp.right = z
          }
        }
        stack[i-1] = z
        return
      }
      if(s._color === BLACK) {
        if(p._color === RED) {
          //console.log("case 2: black sibling, red parent", p.right.value)
          p._color = BLACK
          p.right = repaint(RED, s)
          return
        } else {
          //console.log("case 2: black sibling, black parent", p.right.value)
          p.right = repaint(RED, s)
          continue  
        }
      } else {
        //console.log("case 3: red sibling")
        s = cloneNode(s)
        p.right = s.left
        s.left = p
        s._color = p._color
        p._color = RED
        recount(p)
        recount(s)
        if(i > 1) {
          var pp = stack[i-2]
          if(pp.left === p) {
            pp.left = s
          } else {
            pp.right = s
          }
        }
        stack[i-1] = s
        stack[i] = p
        if(i+1 < stack.length) {
          stack[i+1] = n
        } else {
          stack.push(n)
        }
        i = i+2
      }
    } else {
      //console.log("right child")
      s = p.left
      if(s.left && s.left._color === RED) {
        //console.log("case 1: left sibling child red", p.value, p._color)
        s = p.left = cloneNode(s)
        z = s.left = cloneNode(s.left)
        p.left = s.right
        s.right = p
        s.left = z
        s._color = p._color
        n._color = BLACK
        p._color = BLACK
        z._color = BLACK
        recount(p)
        recount(s)
        if(i > 1) {
          var pp = stack[i-2]
          if(pp.right === p) {
            pp.right = s
          } else {
            pp.left = s
          }
        }
        stack[i-1] = s
        return
      } else if(s.right && s.right._color === RED) {
        //console.log("case 1: right sibling child red")
        s = p.left = cloneNode(s)
        z = s.right = cloneNode(s.right)
        p.left = z.right
        s.right = z.left
        z.right = p
        z.left = s
        z._color = p._color
        p._color = BLACK
        s._color = BLACK
        n._color = BLACK
        recount(p)
        recount(s)
        recount(z)
        if(i > 1) {
          var pp = stack[i-2]
          if(pp.right === p) {
            pp.right = z
          } else {
            pp.left = z
          }
        }
        stack[i-1] = z
        return
      }
      if(s._color === BLACK) {
        if(p._color === RED) {
          //console.log("case 2: black sibling, red parent")
          p._color = BLACK
          p.left = repaint(RED, s)
          return
        } else {
          //console.log("case 2: black sibling, black parent")
          p.left = repaint(RED, s)
          continue  
        }
      } else {
        //console.log("case 3: red sibling")
        s = cloneNode(s)
        p.left = s.right
        s.right = p
        s._color = p._color
        p._color = RED
        recount(p)
        recount(s)
        if(i > 1) {
          var pp = stack[i-2]
          if(pp.right === p) {
            pp.right = s
          } else {
            pp.left = s
          }
        }
        stack[i-1] = s
        stack[i] = p
        if(i+1 < stack.length) {
          stack[i+1] = n
        } else {
          stack.push(n)
        }
        i = i+2
      }
    }
  }
}

//Removes item at iterator from tree
iproto.remove = function() {
  var stack = this._stack
  if(stack.length === 0) {
    return this.tree
  }
  //First copy path to node
  var cstack = new Array(stack.length)
  var n = stack[stack.length-1]
  cstack[cstack.length-1] = new RBNode(n._color, n.key, n.value, n.left, n.right, n._count)
  for(var i=stack.length-2; i>=0; --i) {
    var n = stack[i]
    if(n.left === stack[i+1]) {
      cstack[i] = new RBNode(n._color, n.key, n.value, cstack[i+1], n.right, n._count)
    } else {
      cstack[i] = new RBNode(n._color, n.key, n.value, n.left, cstack[i+1], n._count)
    }
  }

//Get node
  n = cstack[cstack.length-1]
  //console.log("start remove: ", n.value)

//If not leaf, then swap with previous node
  if(n.left && n.right) {
    //console.log("moving to leaf")

//First walk to previous leaf
    var split = cstack.length
    n = n.left
    while(n.right) {
      cstack.push(n)
      n = n.right
    }
    //Copy path to leaf
    var v = cstack[split-1]
    cstack.push(new RBNode(n._color, v.key, v.value, n.left, n.right, n._count))
    cstack[split-1].key = n.key
    cstack[split-1].value = n.value

//Fix up stack
    for(var i=cstack.length-2; i>=split; --i) {
      n = cstack[i]
      cstack[i] = new RBNode(n._color, n.key, n.value, n.left, cstack[i+1], n._count)
    }
    cstack[split-1].left = cstack[split]
  }
  //console.log("stack=", cstack.map(function(v) { return v.value }))

//Remove leaf node
  n = cstack[cstack.length-1]
  if(n._color === RED) {
    //Easy case: removing red leaf
    //console.log("RED leaf")
    var p = cstack[cstack.length-2]
    if(p.left === n) {
      p.left = null
    } else if(p.right === n) {
      p.right = null
    }
    cstack.pop()
    for(var i=0; i<cstack.length; ++i) {
      cstack[i]._count--
    }
    return new RedBlackTree(this.tree._compare, cstack[0])
  } else {
    if(n.left || n.right) {
      //Second easy case:  Single child black parent
      //console.log("BLACK single child")
      if(n.left) {
        swapNode(n, n.left)
      } else if(n.right) {
        swapNode(n, n.right)
      }
      //Child must be red, so repaint it black to balance color
      n._color = BLACK
      for(var i=0; i<cstack.length-1; ++i) {
        cstack[i]._count--
      }
      return new RedBlackTree(this.tree._compare, cstack[0])
    } else if(cstack.length === 1) {
      //Third easy case: root
      //console.log("ROOT")
      return new RedBlackTree(this.tree._compare, null)
    } else {
      //Hard case: Repaint n, and then do some nasty stuff
      //console.log("BLACK leaf no children")
      for(var i=0; i<cstack.length; ++i) {
        cstack[i]._count--
      }
      var parent = cstack[cstack.length-2]
      fixDoubleBlack(cstack)
      //Fix up links
      if(parent.left === n) {
        parent.left = null
      } else {
        parent.right = null
      }
    }
  }
  return new RedBlackTree(this.tree._compare, cstack[0])
}

//Returns key
Object.defineProperty(iproto, "key", {
  get: function() {
    if(this._stack.length > 0) {
      return this._stack[this._stack.length-1].key
    }
    return
  },
  enumerable: true
})

//Returns value
Object.defineProperty(iproto, "value", {
  get: function() {
    if(this._stack.length > 0) {
      return this._stack[this._stack.length-1].value
    }
    return
  },
  enumerable: true
})

//Returns the position of this iterator in the sorted list
Object.defineProperty(iproto, "index", {
  get: function() {
    var idx = 0
    var stack = this._stack
    if(stack.length === 0) {
      var r = this.tree.root
      if(r) {
        return r._count
      }
      return 0
    } else if(stack[stack.length-1].left) {
      idx = stack[stack.length-1].left._count
    }
    for(var s=stack.length-2; s>=0; --s) {
      if(stack[s+1] === stack[s].right) {
        ++idx
        if(stack[s].left) {
          idx += stack[s].left._count
        }
      }
    }
    return idx
  },
  enumerable: true
})

//Advances iterator to next element in list
iproto.next = function() {
  var stack = this._stack
  if(stack.length === 0) {
    return
  }
  var n = stack[stack.length-1]
  if(n.right) {
    n = n.right
    while(n) {
      stack.push(n)
      n = n.left
    }
  } else {
    stack.pop()
    while(stack.length > 0 && stack[stack.length-1].right === n) {
      n = stack[stack.length-1]
      stack.pop()
    }
  }
}

//Checks if iterator is at end of tree
Object.defineProperty(iproto, "hasNext", {
  get: function() {
    var stack = this._stack
    if(stack.length === 0) {
      return false
    }
    if(stack[stack.length-1].right) {
      return true
    }
    for(var s=stack.length-1; s>0; --s) {
      if(stack[s-1].left === stack[s]) {
        return true
      }
    }
    return false
  }
})

//Update value
iproto.update = function(value) {
  var stack = this._stack
  if(stack.length === 0) {
    throw new Error("Can't update empty node!")
  }
  var cstack = new Array(stack.length)
  var n = stack[stack.length-1]
  cstack[cstack.length-1] = new RBNode(n._color, n.key, value, n.left, n.right, n._count)
  for(var i=stack.length-2; i>=0; --i) {
    n = stack[i]
    if(n.left === stack[i+1]) {
      cstack[i] = new RBNode(n._color, n.key, n.value, cstack[i+1], n.right, n._count)
    } else {
      cstack[i] = new RBNode(n._color, n.key, n.value, n.left, cstack[i+1], n._count)
    }
  }
  return new RedBlackTree(this.tree._compare, cstack[0])
}

//Moves iterator backward one element
iproto.prev = function() {
  var stack = this._stack
  if(stack.length === 0) {
    return
  }
  var n = stack[stack.length-1]
  if(n.left) {
    n = n.left
    while(n) {
      stack.push(n)
      n = n.right
    }
  } else {
    stack.pop()
    while(stack.length > 0 && stack[stack.length-1].left === n) {
      n = stack[stack.length-1]
      stack.pop()
    }
  }
}

//Checks if iterator is at start of tree
Object.defineProperty(iproto, "hasPrev", {
  get: function() {
    var stack = this._stack
    if(stack.length === 0) {
      return false
    }
    if(stack[stack.length-1].left) {
      return true
    }
    for(var s=stack.length-1; s>0; --s) {
      if(stack[s-1].right === stack[s]) {
        return true
      }
    }
    return false
  }
})

//Default comparison function
function defaultCompare(a, b) {
  if(a < b) {
    return -1
  }
  if(a > b) {
    return 1
  }
  return 0
}

//Build a tree
function createRBTree(compare) {
  return new RedBlackTree(compare || defaultCompare, null)
}

cmd: