参考链接

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function BinaryHeap(scoreFunction){
this.content = [];
this.scoreFunction = scoreFunction;
}

BinaryHeap.prototype = {
push: function(element) {
// Add the new element to the end of the array.
this.content.push(element);
// Allow it to bubble up.
this.bubbleUp(this.content.length - 1);
},

pop: function() {
// Store the first element so we can return it later.
var result = this.content[0];
// Get the element at the end of the array.
var end = this.content.pop();
// If there are any elements left, put the end element at the
// start, and let it sink down.
if (this.content.length > 0) {
this.content[0] = end;
this.sinkDown(0);
}
return result;
},

remove: function(node) {
var length = this.content.length;
// To remove a value, we must search through the array to find
// it.
for (var i = 0; i < length; i++) {
if (this.content[i] != node) continue;
// When it is found, the process seen in 'pop' is repeated
// to fill up the hole.
var end = this.content.pop();
// If the element we popped was the one we needed to remove,
// we're done.
if (i == length - 1) break;
// Otherwise, we replace the removed element with the popped
// one, and allow it to float up or sink down as appropriate.
this.content[i] = end;
this.bubbleUp(i);
this.sinkDown(i);
break;
}
},

size: function() {
return this.content.length;
},

bubbleUp: function(n) {
// Fetch the element that has to be moved.
var element = this.content[n], score = this.scoreFunction(element);
// When at 0, an element can not go up any further.
while (n > 0) {
// Compute the parent element's index, and fetch it.
var parentN = Math.floor((n + 1) / 2) - 1,
parent = this.content[parentN];
// If the parent has a lesser score, things are in order and we
// are done.
if (score >= this.scoreFunction(parent))
break;

// Otherwise, swap the parent with the current element and
// continue.
this.content[parentN] = element;
this.content[n] = parent;
n = parentN;
}
},

sinkDown: function(n) {
// Look up the target element and its score.
var length = this.content.length,
element = this.content[n],
elemScore = this.scoreFunction(element);

while(true) {
// Compute the indices of the child elements.
var child2N = (n + 1) * 2, child1N = child2N - 1;
// This is used to store the new position of the element,
// if any.
var swap = null;
// If the first child exists (is inside the array)...
if (child1N < length) {
// Look it up and compute its score.
var child1 = this.content[child1N],
child1Score = this.scoreFunction(child1);
// If the score is less than our element's, we need to swap.
if (child1Score < elemScore)
swap = child1N;
}
// Do the same checks for the other child.
if (child2N < length) {
var child2 = this.content[child2N],
child2Score = this.scoreFunction(child2);
if (child2Score < (swap == null ? elemScore : child1Score))
swap = child2N;
}

// No need to swap further, we are done.
if (swap == null) break;

// Otherwise, swap and continue.
this.content[n] = this.content[swap];
this.content[swap] = element;
n = swap;
}
}
};