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package class37;
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import java.util.ArrayList;
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import java.util.Arrays;
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import java.util.Comparator;
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import java.util.LinkedList;
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// 本题测试链接：https://leetcode.com/problems/queue-reconstruction-by-height/
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public class Code04_QueueReconstructionByHeight {
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public static int[][] reconstructQueue1(int[][] people) {
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int N = people.length;
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Unit[] units = new Unit[N];
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for (int i = 0; i < N; i++) {
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units[i] = new Unit(people[i][0], people[i][1]);
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}
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Arrays.sort(units, new UnitComparator());
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ArrayList<Unit> arrList = new ArrayList<>();
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for (Unit unit : units) {
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arrList.add(unit.k, unit);
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}
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int[][] ans = new int[N][2];
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int index = 0;
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for (Unit unit : arrList) {
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ans[index][0] = unit.h;
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ans[index++][1] = unit.k;
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}
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return ans;
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}
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public static int[][] reconstructQueue2(int[][] people) {
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int N = people.length;
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Unit[] units = new Unit[N];
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for (int i = 0; i < N; i++) {
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units[i] = new Unit(people[i][0], people[i][1]);
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}
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Arrays.sort(units, new UnitComparator());
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SBTree tree = new SBTree();
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for (int i = 0; i < N; i++) {
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tree.insert(units[i].k, i);
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}
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LinkedList<Integer> allIndexes = tree.allIndexes();
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int[][] ans = new int[N][2];
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int index = 0;
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for (Integer arri : allIndexes) {
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ans[index][0] = units[arri].h;
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ans[index++][1] = units[arri].k;
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}
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return ans;
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}
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public static class Unit {
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public int h;
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public int k;
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public Unit(int height, int greater) {
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h = height;
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k = greater;
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}
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}
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public static class UnitComparator implements Comparator<Unit> {
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@Override
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public int compare(Unit o1, Unit o2) {
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return o1.h != o2.h ? (o2.h - o1.h) : (o1.k - o2.k);
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}
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}
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public static class SBTNode {
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public int value;
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public SBTNode l;
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public SBTNode r;
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public int size;
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public SBTNode(int arrIndex) {
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value = arrIndex;
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size = 1;
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}
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}
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public static class SBTree {
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private SBTNode root;
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private SBTNode rightRotate(SBTNode cur) {
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SBTNode leftNode = cur.l;
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cur.l = leftNode.r;
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leftNode.r = cur;
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leftNode.size = cur.size;
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cur.size = (cur.l != null ? cur.l.size : 0) + (cur.r != null ? cur.r.size : 0) + 1;
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return leftNode;
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}
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private SBTNode leftRotate(SBTNode cur) {
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SBTNode rightNode = cur.r;
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cur.r = rightNode.l;
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rightNode.l = cur;
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rightNode.size = cur.size;
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cur.size = (cur.l != null ? cur.l.size : 0) + (cur.r != null ? cur.r.size : 0) + 1;
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return rightNode;
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}
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private SBTNode maintain(SBTNode cur) {
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if (cur == null) {
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return null;
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}
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int leftSize = cur.l != null ? cur.l.size : 0;
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int leftLeftSize = cur.l != null && cur.l.l != null ? cur.l.l.size : 0;
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int leftRightSize = cur.l != null && cur.l.r != null ? cur.l.r.size : 0;
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int rightSize = cur.r != null ? cur.r.size : 0;
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int rightLeftSize = cur.r != null && cur.r.l != null ? cur.r.l.size : 0;
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int rightRightSize = cur.r != null && cur.r.r != null ? cur.r.r.size : 0;
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if (leftLeftSize > rightSize) {
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cur = rightRotate(cur);
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cur.r = maintain(cur.r);
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cur = maintain(cur);
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} else if (leftRightSize > rightSize) {
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cur.l = leftRotate(cur.l);
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cur = rightRotate(cur);
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cur.l = maintain(cur.l);
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cur.r = maintain(cur.r);
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cur = maintain(cur);
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} else if (rightRightSize > leftSize) {
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cur = leftRotate(cur);
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cur.l = maintain(cur.l);
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cur = maintain(cur);
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} else if (rightLeftSize > leftSize) {
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cur.r = rightRotate(cur.r);
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cur = leftRotate(cur);
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cur.l = maintain(cur.l);
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cur.r = maintain(cur.r);
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cur = maintain(cur);
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}
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return cur;
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}
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private SBTNode insert(SBTNode root, int index, SBTNode cur) {
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if (root == null) {
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return cur;
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}
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root.size++;
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int leftAndHeadSize = (root.l != null ? root.l.size : 0) + 1;
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if (index < leftAndHeadSize) {
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root.l = insert(root.l, index, cur);
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} else {
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root.r = insert(root.r, index - leftAndHeadSize, cur);
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}
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root = maintain(root);
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return root;
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}
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private SBTNode get(SBTNode root, int index) {
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int leftSize = root.l != null ? root.l.size : 0;
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if (index < leftSize) {
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return get(root.l, index);
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} else if (index == leftSize) {
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return root;
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} else {
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return get(root.r, index - leftSize - 1);
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}
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}
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private void process(SBTNode head, LinkedList<Integer> indexes) {
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if (head == null) {
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return;
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}
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process(head.l, indexes);
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indexes.addLast(head.value);
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process(head.r, indexes);
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}
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public void insert(int index, int value) {
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SBTNode cur = new SBTNode(value);
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if (root == null) {
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root = cur;
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} else {
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if (index <= root.size) {
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root = insert(root, index, cur);
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}
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}
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}
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public int get(int index) {
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SBTNode ans = get(root, index);
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return ans.value;
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}
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public LinkedList<Integer> allIndexes() {
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LinkedList<Integer> indexes = new LinkedList<>();
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process(root, indexes);
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return indexes;
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}
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}
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// 通过以下这个测试，
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// 可以很明显的看到LinkedList的插入和get效率不如SBTree
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// LinkedList需要找到index所在的位置之后才能插入或者读取，时间复杂度O(N)
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// SBTree是平衡搜索二叉树，所以插入或者读取时间复杂度都是O(logN)
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public static void main(String[] args) {
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// 功能测试
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int test = 10000;
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int max = 1000000;
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boolean pass = true;
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LinkedList<Integer> list = new LinkedList<>();
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SBTree sbtree = new SBTree();
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for (int i = 0; i < test; i++) {
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int randomIndex = (int) (Math.random() * (i + 1));
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int randomValue = (int) (Math.random() * (max + 1));
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list.add(randomIndex, randomValue);
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sbtree.insert(randomIndex, randomValue);
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}
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for (int i = 0; i < test; i++) {
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if (list.get(i) != sbtree.get(i)) {
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pass = false;
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break;
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}
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}
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System.out.println("功能测试是否通过 : " + pass);
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// 性能测试
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test = 50000;
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list = new LinkedList<>();
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sbtree = new SBTree();
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long start = 0;
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long end = 0;
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start = System.currentTimeMillis();
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for (int i = 0; i < test; i++) {
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int randomIndex = (int) (Math.random() * (i + 1));
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int randomValue = (int) (Math.random() * (max + 1));
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list.add(randomIndex, randomValue);
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}
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end = System.currentTimeMillis();
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System.out.println("LinkedList插入总时长(毫秒) ： " + (end - start));
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start = System.currentTimeMillis();
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for (int i = 0; i < test; i++) {
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int randomIndex = (int) (Math.random() * (i + 1));
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list.get(randomIndex);
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}
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end = System.currentTimeMillis();
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System.out.println("LinkedList读取总时长(毫秒) : " + (end - start));
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start = System.currentTimeMillis();
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for (int i = 0; i < test; i++) {
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int randomIndex = (int) (Math.random() * (i + 1));
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int randomValue = (int) (Math.random() * (max + 1));
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sbtree.insert(randomIndex, randomValue);
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}
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end = System.currentTimeMillis();
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System.out.println("SBTree插入总时长(毫秒) : " + (end - start));
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start = System.currentTimeMillis();
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for (int i = 0; i < test; i++) {
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int randomIndex = (int) (Math.random() * (i + 1));
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sbtree.get(randomIndex);
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}
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end = System.currentTimeMillis();
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System.out.println("SBTree读取总时长(毫秒) : " + (end - start));
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}
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}
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