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younghohyounghoh
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add Minimize Lateness & Huffman Code
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3 files changed

+328
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‎05/HuffmanCode.java

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package hw05;
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import java.io.BufferedReader;
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import java.io.FileNotFoundException;
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import java.io.FileReader;
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import java.io.IOException;
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import java.util.HashMap;
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import java.util.StringTokenizer;
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public class HuffmanCode {
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private Node[] arr;
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private int heapSize;
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private String str;
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private HashMap<Character, Integer> map;
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private Node huffmanTree;
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public HuffmanCode(String filePath){
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this.str = this.readFile(filePath);
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createFrequencyMap();
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this.arr = new Node[map.size() + 1];
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mapToArr();
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this.heapSize = arr.length - 1;
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doBuildMinHeap(); // 초기 MinHeap 구성
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}
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public void huffmanCode(){
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for(int i = this.heapSize ; i > 1 ; i--) {
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Node left = extractMin(this.arr);
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Node right = extractMin(this.arr);
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Node newNode = new Node(left.getFrequency() + right.getFrequency(), left, right);
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insert(newNode);
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}
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huffmanTree = this.arr[1];
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}
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private void createFrequencyMap(){
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this.map = new HashMap<Character, Integer>();
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String str = this.str;
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for(int i = 0; i < str.length(); i++){
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char character = str.charAt(i);
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if(this.map.containsKey(character)){
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int frequency = this.map.get(character);
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this.map.put(character, ++frequency);
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}else{
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this.map.put(character, 1);
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}
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}
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}
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public void printHuffmanTree(){
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recursionHuffmanTree(huffmanTree, "");
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}
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private void recursionHuffmanTree(Node root, String code){
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if(root != null){
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if(root.getLeft() != null && root.getRight() != null){
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recursionHuffmanTree(root.getLeft(), code + "0");
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recursionHuffmanTree(root.getRight(), code + "1");
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}
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else{
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System.out.println(root.getAlphabet() + ", " + code);
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}
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}
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}
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private void insert(Node x){
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Node[] temp = new Node[this.heapSize + 2];
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for(int i = 1 ; i <= this.heapSize; i++){
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temp[i] = arr[i];
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}
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temp[temp.length - 1] = x;
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this.arr = temp;
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this.heapSize = temp.length - 1;
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buildMinHeap(this.arr);
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}
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private void mapToArr(){
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int i = 1;
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for(HashMap.Entry<Character, Integer> elem : map.entrySet()){
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arr[i] = new Node(elem.getKey(), elem.getValue());
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i++;
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}
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}
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private Node extractMin(Node[] arr){
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Node minNode = arr[1];
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swap(arr, heapSize, 1);
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this.heapSize--;
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doBuildMinHeap();
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return minNode;
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}
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public void doBuildMinHeap(){
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buildMinHeap(this.arr);
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}
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private void buildMinHeap(Node[] arr){
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for(int i = (this.heapSize) / 2 ; i > 0 ; i--){
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minHeapify(arr, i);
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}
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}
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private void minHeapify(Node[] arr, int i){
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int smallest;
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int leftChildIdx = getLeftChildIdx(i);
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int rightChildIdx = getRightChildIdx(i);
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if(this.heapSize >= leftChildIdx && arr[leftChildIdx].frequency < arr[i].frequency){
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smallest = leftChildIdx;
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}else{
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smallest = i;
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}
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if(this.heapSize >= rightChildIdx && arr[rightChildIdx].frequency < arr[smallest].frequency){
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smallest = rightChildIdx;
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}
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if(smallest != i){
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swap(arr, smallest, i);
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minHeapify(arr, smallest);
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}
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}
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private void swap(Node[] arr, int i, int j){
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Node temp = arr[i];
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arr[i] = arr[j];
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arr[j] = temp;
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}
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private int getLeftChildIdx(int parentIdx){
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return 2*parentIdx;
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}
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private int getRightChildIdx(int parentIdx){
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return 2*parentIdx+1;
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}
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private String readFile(String filePath) {
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BufferedReader br = null;
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StringTokenizer str = null;
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StringBuilder sb = null;
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String line;
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try {
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br = new BufferedReader(new FileReader(filePath));
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sb = new StringBuilder();
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while ((line = br.readLine()) != null) {
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sb.append(line);
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}
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} catch (FileNotFoundException e) {
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e.printStackTrace();
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} catch (IOException e) {
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e.printStackTrace();
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} finally {
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if (br != null) {
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try {
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br.close();
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} catch (IOException e) {
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e.printStackTrace();
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}
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}
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return sb.toString();
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}
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}
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class Node{
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private Node left, right;
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private char alphabet;
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private int frequency;
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public Node(char alphabet, int frequency){
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this.alphabet = alphabet;
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this.frequency = frequency;
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this.left = null;
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this.right = null;
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}
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public Node(int frequency, Node left, Node right){
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this.alphabet = ' ';
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this.frequency = frequency;
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this.left = left;
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this.right = right;
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}
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public Node(char alphabet, int frequency, Node left, Node right){
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this.alphabet = alphabet;
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this.frequency = frequency;
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this.left = left;
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this.right = right;
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}
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public Node getLeft() {
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return left;
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}
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public Node getRight() {
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return right;
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}
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public char getAlphabet() {
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return alphabet;
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}
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public int getFrequency() {
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return frequency;
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}
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}
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}

‎05/MinimizeLateness.java

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package hw05;
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import java.io.BufferedReader;
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import java.io.FileNotFoundException;
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import java.io.FileReader;
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import java.io.IOException;
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import java.util.StringTokenizer;
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import static java.lang.Math.max;
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public class MinimizeLateness {
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private Job[] arr;
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public MinimizeLateness(String filePath){
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String data = this.readFile(filePath);
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StringTokenizer str = new StringTokenizer(data, " |\n");
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arr = new Job[Integer.parseInt(str.nextToken())];
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for(int i = 0; str.hasMoreTokens(); i++){
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arr[i] = new Job(Integer.parseInt(str.nextToken()), Integer.parseInt(str.nextToken()));
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}
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}
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public int doMinimizeLateness(){
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return minimizeLateness(this.arr);
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}
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private int minimizeLateness(Job[] arr){
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quickSort(arr, 0, arr.length-1);
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int time = 0;
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int lateness = 0;
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for(int i = 0; i<arr.length; i++){
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int startTime = time;
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int takingTime = arr[i].getJobTakingTime();
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int scheduledEndTime = arr[i].getDeadLineTime();
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int finishTime = time + takingTime;
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time = finishTime;
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lateness = max(lateness, finishTime - scheduledEndTime);
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}
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return lateness;
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}
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private int partition(Job[] arr, int p, int r){
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int target = arr[r].getDeadLineTime();
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int i = p-1;
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int j = p;
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while(j <= r-1){ // j가 끝 인덱스 전까지 탐색하도록
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if(arr[j].getDeadLineTime() <= target){
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i++;
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swap(arr, i, j);
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}
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j++;
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}
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i++;
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swap(arr, i, j);
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return i;
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}
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private void swap(Job[] arr, int i, int j){
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Job temp = arr[i];
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arr[i] = arr[j];
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arr[j] = temp;
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}
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private void quickSort(Job[] arr, int p, int r){
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if(p < r){
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int pivotIndex = partition(arr, p, r);
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quickSort(arr, p, pivotIndex-1);
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quickSort(arr, pivotIndex+1, r);
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}
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}
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private String readFile(String filePath) {
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BufferedReader br = null;
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StringTokenizer str = null;
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StringBuilder sb = null;
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String line;
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try {
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br = new BufferedReader(new FileReader(filePath));
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sb = new StringBuilder();
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while ((line = br.readLine()) != null) {
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sb.append(line+"\n");
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}
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} catch (FileNotFoundException e) {
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e.printStackTrace();
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} catch (IOException e) {
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e.printStackTrace();
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} finally {
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if (br != null) {
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try {
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br.close();
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} catch (IOException e) {
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e.printStackTrace();
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}
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}
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return sb.toString();
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}
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}
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class Job{
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private int jobTakingTime, deadLineTime;
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public Job(int time, int deadLine){
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this.jobTakingTime = time;
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this.deadLineTime = deadLine;
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}
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private int getJobTakingTime(){
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return jobTakingTime;
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}
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private int getDeadLineTime(){
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return deadLineTime;
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}
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}
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}
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‎README.md

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# Algorithm
2-
*****
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1. BinaryInsertionSort / InsertionSort / MergeSort
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2. HeapSort / QuickSort
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3. Closest Pair of Points / Loop Invariant
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4. Counting Inversion / Karatsuba
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5. Minimize Lateness / Huffman Code

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