feat(csharp) .NET 8.0 code migration (#966)

* .net 8.0 migration

* update docs

* revert change

* revert change and update appendix docs

* remove static

* Update binary_search_insertion.cs

* Update binary_search_insertion.cs

* Update binary_search_edge.cs

* Update binary_search_insertion.cs

* Update binary_search_edge.cs

---------

Co-authored-by: Yudong Jin <krahets@163.com>

codes/csharp/chapter_greedy/coin_change_greedy.cs

@@ -8,7 +8,7 @@ namespace hello_algo.chapter_greedy;
 
 public class coin_change_greedy {
     /* 零钱兑换：贪心 */
-    public int CoinChangeGreedy(int[] coins, int amt) {
+    int CoinChangeGreedy(int[] coins, int amt) {
         // 假设 coins 列表有序
         int i = coins.Length - 1;
         int count = 0;
@@ -29,14 +29,14 @@ public class coin_change_greedy {
     [Test]
     public void Test() {
         // 贪心：能够保证找到全局最优解
-        int[] coins = { 1, 5, 10, 20, 50, 100 };
+        int[] coins = [1, 5, 10, 20, 50, 100];
         int amt = 186;
         int res = CoinChangeGreedy(coins, amt);
         Console.WriteLine("\ncoins = " + coins.PrintList() + ", amt = " + amt);
         Console.WriteLine("凑到 " + amt + " 所需的最少硬币数量为 " + res);
 
         // 贪心：无法保证找到全局最优解
-        coins = new int[] { 1, 20, 50 };
+        coins = [1, 20, 50];
         amt = 60;
         res = CoinChangeGreedy(coins, amt);
         Console.WriteLine("\ncoins = " + coins.PrintList() + ", amt = " + amt);
@@ -44,7 +44,7 @@ public class coin_change_greedy {
         Console.WriteLine("实际上需要的最少数量为 3 ，即 20 + 20 + 20");
 
         // 贪心：无法保证找到全局最优解
-        coins = new int[] { 1, 49, 50 };
+        coins = [1, 49, 50];
         amt = 98;
         res = CoinChangeGreedy(coins, amt);
         Console.WriteLine("\ncoins = " + coins.PrintList() + ", amt = " + amt);

codes/csharp/chapter_greedy/fractional_knapsack.cs

@@ -7,19 +7,14 @@
 namespace hello_algo.chapter_greedy;
 
 /* 物品 */
-class Item {
-    public int w; // 物品重量
-    public int v; // 物品价值
-
-    public Item(int w, int v) {
-        this.w = w;
-        this.v = v;
-    }
+class Item(int w, int v) {
+    public int w = w; // 物品重量
+    public int v = v; // 物品价值
 }
 
 public class fractional_knapsack {
     /* 分数背包：贪心 */
-    public double FractionalKnapsack(int[] wgt, int[] val, int cap) {
+    double FractionalKnapsack(int[] wgt, int[] val, int cap) {
         // 创建物品列表，包含两个属性：重量、价值
         Item[] items = new Item[wgt.Length];
         for (int i = 0; i < wgt.Length; i++) {
@@ -46,8 +41,8 @@ public class fractional_knapsack {
 
     [Test]
     public void Test() {
-        int[] wgt = { 10, 20, 30, 40, 50 };
-        int[] val = { 50, 120, 150, 210, 240 };
+        int[] wgt = [10, 20, 30, 40, 50];
+        int[] val = [50, 120, 150, 210, 240];
         int cap = 50;
 
         // 贪心算法

codes/csharp/chapter_greedy/max_capacity.cs

@@ -8,7 +8,7 @@ namespace hello_algo.chapter_greedy;
 
 public class max_capacity {
     /* 最大容量：贪心 */
-    public int MaxCapacity(int[] ht) {
+    int MaxCapacity(int[] ht) {
         // 初始化 i, j 分列数组两端
         int i = 0, j = ht.Length - 1;
         // 初始最大容量为 0
@@ -30,7 +30,7 @@ public class max_capacity {
 
     [Test]
     public void Test() {
-        int[] ht = { 3, 8, 5, 2, 7, 7, 3, 4 };
+        int[] ht = [3, 8, 5, 2, 7, 7, 3, 4];
 
         // 贪心算法
         int res = MaxCapacity(ht);

codes/csharp/chapter_greedy/max_product_cutting.cs

@@ -8,7 +8,7 @@ namespace hello_algo.chapter_greedy;
 
 public class max_product_cutting {
     /* 最大切分乘积：贪心 */
-    public int MaxProductCutting(int n) {
+    int MaxProductCutting(int n) {
         // 当 n <= 3 时，必须切分出一个 1
         if (n <= 3) {
             return 1 * (n - 1);