tdubs42/linked-list-class.js

## linked-list-class.js
const Node = require('./Node');

class LinkedList {
  constructor() {
    this.head = null;
  }

  addToHead(data) {
    const newHead = new Node(data);
    const currentHead = this.head;
    this.head = newHead;
    if (currentHead) {
      this.head.setNextNode(currentHead);
    }
  }

  addToTail(data) {
    let tail = this.head;
    if (!tail) {
      this.head = new Node(data);
    } else {
      while (tail.getNextNode() !== null) {
        tail = tail.getNextNode();
      }
      tail.setNextNode(new Node(data));
    }
  }

  removeHead() {
    const removedHead = this.head;
    if (!removedHead) {
      return;
    }
    if (removedHead.next) {
      this.head = removedHead.getNextNode();
    }
    return removedHead.data;
  }

  printList() {
    let currentNode = this.head;
    let output = '<head> ';
    while (currentNode !== null) {
      output += currentNode.data + ' ';
      currentNode = currentNode.getNextNode();
    }
    output += `<tail>`;
    console.log(output);
  }

  findNodeIteratively(data) {
    let currentNode = this.head;
    while (currentNode !== null) {
      if (currentNode.data === data) {
        return currentNode;
      }
      currentNode = currentNode.getNextNode();
    }
    return null;
  }

  findNodeRecursively(data, currentNode = this.head) {
    if (currentNode === null) {
      return null;
    } else if (currentNode.data === data) {
      return currentNode;
    } else {
      return this.findNodeRecursively(data, currentNode.getNextNode());
    }
  }

}

module.exports = LinkedList;
	const Node = require('./Node');

	class LinkedList {
	constructor() {
	this.head = null;
	}

	addToHead(data) {
	const newHead = new Node(data);
	const currentHead = this.head;
	this.head = newHead;
	if (currentHead) {
	this.head.setNextNode(currentHead);
	}
	}

	addToTail(data) {
	let tail = this.head;
	if (!tail) {
	this.head = new Node(data);
	} else {
	while (tail.getNextNode() !== null) {
	tail = tail.getNextNode();
	}
	tail.setNextNode(new Node(data));
	}
	}

	removeHead() {
	const removedHead = this.head;
	if (!removedHead) {
	return;
	}
	if (removedHead.next) {
	this.head = removedHead.getNextNode();
	}
	return removedHead.data;
	}

	printList() {
	let currentNode = this.head;
	let output = '<head> ';
	while (currentNode !== null) {
	output += currentNode.data + ' ';
	currentNode = currentNode.getNextNode();
	}
	output += `<tail>`;
	console.log(output);
	}

	findNodeIteratively(data) {
	let currentNode = this.head;
	while (currentNode !== null) {
	if (currentNode.data === data) {
	return currentNode;
	}
	currentNode = currentNode.getNextNode();
	}
	return null;
	}

	findNodeRecursively(data, currentNode = this.head) {
	if (currentNode === null) {
	return null;
	} else if (currentNode.data === data) {
	return currentNode;
	} else {
	return this.findNodeRecursively(data, currentNode.getNextNode());
	}
	}

	}

	module.exports = LinkedList;