Add cpp codes for the chapter

computational complexity, sorting, searching.

codes/java/chapter_computational_complexity/space_complexity_types.java

@@ -59,7 +59,7 @@ public class space_complexity_types {
     /* 平方阶 */
     static void quadratic(int n) {
         // 矩阵占用 O(n^2) 空间
-        int numMatrix[][] = new int[n][n];
+        int[][] numMatrix = new int[n][n];
         // 二维列表占用 O(n^2) 空间
         List<List<Integer>> numList = new ArrayList<>();
         for (int i = 0; i < n; i++) {

codes/java/chapter_searching/hashing_search.java

@@ -20,7 +20,7 @@ public class hashing_search {
     /* 哈希查找（链表） */
     static ListNode hashingSearch1(Map<Integer, ListNode> map, int target) {
         // 哈希表的 key: 目标结点值，value: 结点对象
-        // 若哈希表中无此 key ，返回 -1
+        // 若哈希表中无此 key ，返回 null
         return map.getOrDefault(target, null);
     }
 

codes/java/chapter_searching/linear_search.java

@@ -9,7 +9,6 @@ package chapter_searching;
 import include.*;
 
 public class linear_search {
-
     /* 线性查找（数组） */
     static int linearSearch(int[] nums, int target) {
         // 遍历数组

codes/java/chapter_sorting/bubble_sort.java

@@ -47,10 +47,10 @@ public class bubble_sort {
     public static void main(String[] args) {
         int[] nums = { 4, 1, 3, 1, 5, 2 };
         bubbleSort(nums);
-        System.out.println("排序后数组 nums = " + Arrays.toString(nums));
+        System.out.println("冒泡排序完成后 nums = " + Arrays.toString(nums));
 
         int[] nums1 = { 4, 1, 3, 1, 5, 2 };
         bubbleSortWithFlag(nums1);
-        System.out.println("排序后数组 nums1 = " + Arrays.toString(nums));
+        System.out.println("冒泡排序完成后 nums1 = " + Arrays.toString(nums));
     }
 }

codes/java/chapter_sorting/insertion_sort.java

@@ -26,6 +26,6 @@ public class insertion_sort {
     public static void main(String[] args) {
         int[] nums = { 4, 1, 3, 1, 5, 2 };
         insertionSort(nums);
-        System.out.println("排序后数组 nums = " + Arrays.toString(nums));
+        System.out.println("插入排序完成后 nums = " + Arrays.toString(nums));
     }
 }

codes/java/chapter_sorting/merge_sort.java

@@ -51,7 +51,7 @@ public class merge_sort {
 
     public static void main(String[] args) {
         /* 归并排序 */
-        int[] nums = { 2, 4, 1, 0, 3, 5 };
+        int[] nums = { 7, 3, 2, 6, 0, 1, 5, 4 };
         mergeSort(nums, 0, nums.length - 1);
         System.out.println("归并排序完成后 nums = " + Arrays.toString(nums));
     }