小编典典

如何在Javascript中检索基数字典中的所有数据/单词

algorithm

我已经能够用JavaScript制作一个Radix树示例(未优化,所以不要判断)

到目前为止,我已经能够AddTransverseFind节点。

我在编写一个可以retrieve覆盖所有节点的函数时遇到了麻烦,这是我需要帮助的地方。在此先感谢您

// As illustrated in:
// http://programminggeeks.com/c-code-for-radix-tree-or-trie/

// Make a class of the Tree so that you can define methods all nodes of the tree
// which are actually Trees in structure inherit the functions
function Tree() {
    this.character = undefined;

    // if this node is the end of a complete word
    // this was we can differentiate "sell" and "sells" if both are searched for
    this.isword = false;

    // How to nest the nodes, thus creating a tree structure
    this.node = {}; // [new Tree(), new Tree(), new Tree()];

    // abcdefghijklmnopqrstuvwxyz
    var start = 97,
        end = start + 25;

    function constructor(that) {
        for (var x = start; x <= end; x++) {
            // for now they are all unsigned objects
            that.node[x] = null // new Tree()
        }
        return that;
    }

    constructor(this);
    return this;
}

Tree.prototype.addNode = function(word) {
    return this.transverseNodes(word, true);
};

Tree.prototype.searchForNodes = function(word) {
    return this.transverseNodes(word, false);
};

Tree.prototype.stringToNodes = function(word) {
    var nodeArray = []
    for (var x = 0, length = word.length; x < length; x++) {
        nodeArray.push(word.charCodeAt(x));
    }
    return nodeArray;
};

Tree.prototype.transverseNodes = function(word, bool) {
    // make all of the letters lowercase to create uniformity
    var nodes = this.stringToNodes(word.toLowerCase());
    // console.log(nodes);

    // start with parent/root tree
    var currentTreeNode = this

    // transverse checking if node has been added, if not add it
    // if it was already added and it terminates a word set it "isword" property to true
    for (var i = 0, length = nodes.length; i < length; i++) {
        var node = nodes[i];

        // If the current tree node is defined so not overwrite it
        if (currentTreeNode.node[node] === null) {

            if (!bool) {
                // if bool is undefined of false, then this is a search
                return false;
            }

            // create a node
            currentTreeNode.node[node] = new Tree();
            currentTreeNode.node[node].character = String.fromCharCode(node);
        }

        // check if the node is the last character of the word
        if ((nodes.length - 1) === i) {
            // console.log(nodes.length - 1, i)
            if (!bool) {
                // if bool is undefined of false, then this is a search
                return true;
            }

            currentTreeNode.node[node].isword = true;
        }

        // get into the nested node
        currentTreeNode = currentTreeNode.node[node];
    };

    return this;
};

var tree = new Tree()

// Create the nodes
tree.addNode("cat");
tree.addNode("camel");
tree.addNode("condom");
tree.addNode("catastrophe");
tree.addNode("grandma");
tree.addNode("lamboghini");

// Search the nodes
console.log(tree.searchForNodes("cat")); // true
console.log(tree.searchForNodes("catapult")); // false
console.log(tree.searchForNodes("catastrophe")); // true
console.log(tree.searchForNodes("mama")); // false
console.log(tree.searchForNodes("lamboghini")); // true

// retrieving all node
// console.log(tree.retrieveAllNodes());

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2020-07-28

共1个答案

小编典典

该建议采用一种迭代和递归的方法来获取树中的单词。

'use strict';

// As illustrated in:

// http://programminggeeks.com/c-code-for-radix-tree-or-trie/



// Make a class of the Tree so that you can define methods all nodes of the tree

// which are actually Trees in structure inherit the functions

function Tree() {

    this.character = undefined;



    // if this node is the end of a complete word

    // this was we can differentiate "sell" and "sells" if both are searched for

    this.isword = false;



    // How to nest the nodes, thus creating a tree structure

    this.node = {}; // [new Tree(), new Tree(), new Tree()];



    // abcdefghijklmnopqrstuvwxyz

    var start = 97,

        end = start + 25;



    function constructor(that) {

        for (var x = start; x <= end; x++) {

            // for now they are all unsigned objects

            that.node[x] = null // new Tree()

        }

        return that;

    }



    constructor(this);

    return this;

}



Tree.prototype.addNode = function (word) {

    return this.transverseNodes(word, true);

};



Tree.prototype.searchForNodes = function (word) {

    return this.transverseNodes(word, false);

};



Tree.prototype.stringToNodes = function (word) {

    var nodeArray = []

    for (var x = 0, length = word.length; x < length; x++) {

        nodeArray.push(word.charCodeAt(x));

    }

    return nodeArray;

};



Tree.prototype.transverseNodes = function (word, bool) {

    // make all of the letters lowercase to create uniformity

    var nodes = this.stringToNodes(word.toLowerCase());

    // console.log(nodes);



    // start with parent/root tree

    var currentTreeNode = this



    // transverse checking if node has been added, if not add it

    // if it was already added and it terminates a word set it "isword" property to true

    for (var i = 0, length = nodes.length; i < length; i++) {

        var node = nodes[i];



        // If the current tree node is defined so not overwrite it

        if (currentTreeNode.node[node] === null) {



            if (!bool) {

                // if bool is undefined of false, then this is a search

                return false;

            }



            // create a node

            currentTreeNode.node[node] = new Tree();

            currentTreeNode.node[node].character = String.fromCharCode(node);

        }



        // check if the node is the last character of the word

        if ((nodes.length - 1) === i) {

            // console.log(nodes.length - 1, i)

            if (!bool) {

                // if bool is undefined of false, then this is a search

                return true;

            }

            currentTreeNode.node[node].isword = true;

        }



        // get into the nested node

        currentTreeNode = currentTreeNode.node[node];

    };



    return this;

};



Tree.prototype.retrieveAllNodes = function () {



    // function for traversing over object, takes the object and an empty string for

    // the appearing words, acts as closure for the object

    function iterObject(o, r) {

        // how i like to start functions with return (...)

        // returns basically the up coming word.

        // reason for reduce, this provides a return value, with the letters

        // of the path

        return Object.keys(o).reduce(function (r, key) {

            // check if the key property has a truthy value (remember the default

            // null values)

            if (o[key]) {

                // if so, check the property isword

                if (o[key].isword) {

                    // if its truty here, we have a hit, a word is found

                    wordList.push(r + o[key].character);

                };

                // check for children

                if (o[key].node) {

                    // if node exist, go on with a new iteration and a new word

                    // extension

                    iterObject(o[key].node, r + o[key].character);

                }

            }

            // return the inevitable word stem

            return r;

        }, r);

    }



    var wordList = [];

    iterObject(this.node, '');

    return wordList;

}



var tree = new Tree();



// Create the nodes

tree.addNode("cat");

tree.addNode("camel");

tree.addNode("condom");

tree.addNode("catastrophe");

tree.addNode("grandma");

tree.addNode("lamboghini");



// Search the nodes

console.log(tree.searchForNodes("cat"));         // true

console.log(tree.searchForNodes("catapult"));    // false

console.log(tree.searchForNodes("catastrophe")); // true

console.log(tree.searchForNodes("mama"));        // false

console.log(tree.searchForNodes("lamboghini"));  // true



// retrieving all words

console.log(JSON.stringify(tree.retrieveAllNodes(), 0, 4));

// retrieving whole tree

console.log(JSON.stringify(tree, 0, 4));


.as-console-wrapper { max-height: 100% !important; top: 0; }

奖励:以下是开销很小的版本。

'use strict';

function Tree() {

    return this;

}



Tree.prototype.addNode = function (word) {

    this.stringToNodes(word).reduce(function (node, character, i, a) {

        if (!node[character]) {

            node[character] = {};

        }

        if (i === a.length - 1) {

            node[character].isword = true;

        }

        return node[character];

    }, this);

    return this;

};



Tree.prototype.searchForNodes = function (word) {



    function iterObject(o, r) {

        return Object.keys(o).reduce(function (r, key) {

            if (key === 'isword' && r === word) {

                found = true;

            }

            typeof o[key] === 'object' && iterObject(o[key], r + key);

            return r;

        }, r);

    }



    var found = false;

    iterObject(this, '');

    return found;

};





Tree.prototype.stringToNodes = function (word) {

    return word.toLowerCase().split('');

};



Tree.prototype.retrieveAllNodes = function () {



    function iterObject(o, r) {

        return Object.keys(o).reduce(function (r, key) {

            key === 'isword' && wordList.push(r);

            typeof o[key] === 'object' && iterObject(o[key], r + key);

            return r;

        }, r);

    }



    var wordList = [];

    iterObject(this, '');

    return wordList;

}



var tree = new Tree();



// Create the nodes

tree.addNode("cat");

tree.addNode("camel");

tree.addNode("condom");

tree.addNode("catastrophe");

tree.addNode("grandma");

tree.addNode("lamboghini");



// Search the nodes

console.log(tree.searchForNodes("cat"));         // true

console.log(tree.searchForNodes("catapult"));    // false

console.log(tree.searchForNodes("catastrophe")); // true

console.log(tree.searchForNodes("mama"));        // false

console.log(tree.searchForNodes("lamboghini"));  // true



// retrieving all words

console.log(JSON.stringify(tree.retrieveAllNodes(), 0, 4));

// retrieving whole tree

console.log(JSON.stringify(tree, 0, 4));


.as-console-wrapper { max-height: 100% !important; top: 0; }
2020-07-28