(function (exports) {

/**

* Checks whether path between two nodes exists.

* The initialization has O(n) complexity.

*

* @constructor

* @param {number} n Nodes count

*

*/

function QuickUnion(n) {

this._ids = [];

for (var i = 0; i < n; i += 1) {

this._ids[i] = i;

}

}

/**

* Finds the root of given node.

* Complexity O(n).

*

* @param {number} i The given node

* @return {number} The root of the given node

*/

QuickUnion.prototype._root = function (i) {

while (i !== this._ids[i]) i = this._ids[i];

return i;

};

/**

* Unions two nodes.

* Complexity O(n).

*

* @param {number} p The first node

* @param {number} q The second node

*/

QuickUnion.prototype.union = function (p, q) {

var pRoot = this._root(p),

qRoot = this._root(q);

this._ids[pRoot] = qRoot;

};

/**

* Checks whether two nodes are connected.

* Complexity O(n).

*

* @param {number} p The first node.

* @param {number} q The second node.

* @return {boolean} True/false depending on whether the nodes are connected.

*/

QuickUnion.prototype.connected = function (p, q) {

return this._root(p) === this._root(q);

};

//var union = new QuickUnion(10);

//union.union(0, 1);

//union.union(2, 1);

//union.union(3, 4);

//union.union(8, 9);

//union.union(4, 8);

//

//console.log(union.connected(0, 9)); //expected false

//console.log(union.connected(3, 9)); //expected true

exports.QuickUnion = QuickUnion;

}(typeof exports === 'undefined' ? window : exports));