数据结构_中国大学MOOC-数据结构-4.3

1题目：Huffman Codes

http://www.patest.cn/contests/mooc-ds/04-3

import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.util.ArrayList;
import java.util.Collections;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
import java.util.PriorityQueue;
import java.util.Queue;

public class Main {
    public static void main(String args[]) throws NumberFormatException,
            IOException {
        BufferedReader in = new BufferedReader(new InputStreamReader(System.in));
        int N = Integer.parseInt(in.readLine()); // 存储键值对的个数
        String[] line = in.readLine().split(" ");
        Map<String, Integer> map = new HashMap<String, Integer>();// 存储A 1 B 1 C
                                                                    // 1 D 3 E 3
                                                                    // F 6 G
                                                                    // 6的键值对
        Queue<Integer> priorityQueue = new PriorityQueue<Integer>(N);// 使用优先级列队模拟堆

        for (int i = 0; i < N; i++) {
            map.put(line[2 * i], Integer.parseInt(line[2 * i + 1]));
            priorityQueue.add(Integer.parseInt(line[2 * i + 1]));
        }
        /* 计算Wpl的值 */
        int Wpl = 0;
        while (!priorityQueue.isEmpty()) {
            int top1 = priorityQueue.poll();
            if (!priorityQueue.isEmpty()) {
                int top2 = priorityQueue.poll();
                int temp = top1 + top2;
                priorityQueue.add(temp);
                Wpl += temp;
            }
        }
        // 输入测试数据

        int CheckN = Integer.parseInt(in.readLine());
        for (int i = 0; i < CheckN; i++) {
            Test[] test = new Test[N];
            int wpl2 = 0;
            String[] read;
            List<Test> array = new ArrayList<Test>();
            for (int j = 0; j < N; j++) {
                read = in.readLine().split(" ");
                test[j] = new Test();
                test[j].a = read[0];
                test[j].s = read[1];
                array.add(test[j]);
                wpl2 += read[1].length() * map.get(read[0]);
            }
            Collections.sort(array);
            if (Wpl != wpl2) {
                System.out.println("No");
                continue;
            } else {
                boolean flag = true;
                for (int n = 0; n < N - 1; n++) {
                    String tmp = array.get(n).s;
                    for (int m = n + 1; m < N; m++) {
                        if (array.get(m).s.substring(0, tmp.length()).equals(
                                tmp)) {
                            flag = false;
                        }
                    }
                }
                if (flag) {
                    System.out.println("Yes");
                } else {
                    System.out.println("No");
                }
            }

        }

    }

}

class Test implements Comparable {
    String a;
    String s;

    public String getA() {
        return a;
    }

    public void setA(String a) {
        this.a = a;
    }

    public String getS() {
        return s;
    }

    public void setS(String s) {
        this.s = s;
    }

    @Override
    public int compareTo(Object o) {
        // TODO Auto-generated method stub
        return this.s.length() - ((Test) o).s.length();
    }
}