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Reformat the C# codes.

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Disable creating new line before open brace.
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krahets
2023-04-23 03:03:12 +08:00
parent ac6eece4f3
commit 73dcb4cea9
49 changed files with 561 additions and 1135 deletions
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99
codes/csharp/chapter_computational_complexity/time_complexity.cs
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@ -8,52 +8,41 @@ using NUnit.Framework;
namespace hello_algo.chapter_computational_complexity;
public class time_complexity
{
void algorithm(int n)
{
public class time_complexity {
void algorithm(int n) {
int a = 1; // +0（技巧 1）
a = a + n; // +0（技巧 1）
// +n（技巧 2）
for (int i = 0; i < 5 * n + 1; i++)
{
for (int i = 0; i < 5 * n + 1; i++) {
Console.WriteLine(0);
}
// +n*n（技巧 3）
for (int i = 0; i < 2 * n; i++)
{
for (int j = 0; j < n + 1; j++)
{
for (int i = 0; i < 2 * n; i++) {
for (int j = 0; j < n + 1; j++) {
Console.WriteLine(0);
}
}
}
// 算法 A 时间复杂度：常数阶
void algorithm_A(int n)
{
void algorithm_A(int n) {
Console.WriteLine(0);
}
// 算法 B 时间复杂度：线性阶
void algorithm_B(int n)
{
for (int i = 0; i < n; i++)
{
void algorithm_B(int n) {
for (int i = 0; i < n; i++) {
Console.WriteLine(0);
}
}
// 算法 C 时间复杂度：常数阶
void algorithm_C(int n)
{
for (int i = 0; i < 1000000; i++)
{
void algorithm_C(int n) {
for (int i = 0; i < 1000000; i++) {
Console.WriteLine(0);
}
}
/* 常数阶 */
static int constant(int n)
{
static int constant(int n) {
int count = 0;
int size = 100000;
for (int i = 0; i < size; i++)
@ -62,8 +51,7 @@ public class time_complexity
}
/* 线性阶 */
static int linear(int n)
{
static int linear(int n) {
int count = 0;
for (int i = 0; i < n; i++)
count++;
@ -71,26 +59,21 @@ public class time_complexity
}
/* 线性阶（遍历数组） */
static int arrayTraversal(int[] nums)
{
static int arrayTraversal(int[] nums) {
int count = 0;
// 循环次数与数组长度成正比
foreach (int num in nums)
{
foreach (int num in nums) {
count++;
}
return count;
}
/* 平方阶 */
static int quadratic(int n)
{
static int quadratic(int n) {
int count = 0;
// 循环次数与数组长度成平方关系
for (int i = 0; i < n; i++)
{
for (int j = 0; j < n; j++)
{
for (int i = 0; i < n; i++) {
for (int j = 0; j < n; j++) {
count++;
}
}
@ -98,17 +81,13 @@ public class time_complexity
}
/* 平方阶（冒泡排序） */
static int bubbleSort(int[] nums)
{
static int bubbleSort(int[] nums) {
int count = 0; // 计数器
// 外循环：待排序元素数量为 n-1, n-2, ..., 1
for (int i = nums.Length - 1; i > 0; i--)
{
for (int i = nums.Length - 1; i > 0; i--) {
// 内循环：冒泡操作
for (int j = 0; j < i; j++)
{
if (nums[j] > nums[j + 1])
{
for (int j = 0; j < i; j++) {
if (nums[j] > nums[j + 1]) {
// 交换 nums[j] 与 nums[j + 1]
int tmp = nums[j];
nums[j] = nums[j + 1];
@ -121,14 +100,11 @@ public class time_complexity
}
/* 指数阶（循环实现） */
static int exponential(int n)
{
static int exponential(int n) {
int count = 0, bas = 1;
// cell 每轮一分为二，形成数列 1, 2, 4, 8, ..., 2^(n-1)
for (int i = 0; i < n; i++)
{
for (int j = 0; j < bas; j++)
{
for (int i = 0; i < n; i++) {
for (int j = 0; j < bas; j++) {
count++;
}
bas *= 2;
@ -138,18 +114,15 @@ public class time_complexity
}
/* 指数阶（递归实现） */
static int expRecur(int n)
{
static int expRecur(int n) {
if (n == 1) return 1;
return expRecur(n - 1) + expRecur(n - 1) + 1;
}
/* 对数阶（循环实现） */
static int logarithmic(float n)
{
static int logarithmic(float n) {
int count = 0;
while (n > 1)
{
while (n > 1) {
n = n / 2;
count++;
}
@ -157,41 +130,35 @@ public class time_complexity
}
/* 对数阶（递归实现） */
static int logRecur(float n)
{
static int logRecur(float n) {
if (n <= 1) return 0;
return logRecur(n / 2) + 1;
}
/* 线性对数阶 */
static int linearLogRecur(float n)
{
static int linearLogRecur(float n) {
if (n <= 1) return 1;
int count = linearLogRecur(n / 2) +
linearLogRecur(n / 2);
for (int i = 0; i < n; i++)
{
for (int i = 0; i < n; i++) {
count++;
}
return count;
}
/* 阶乘阶（递归实现） */
static int factorialRecur(int n)
{
static int factorialRecur(int n) {
if (n == 0) return 1;
int count = 0;
// 从 1 个分裂出 n 个
for (int i = 0; i < n; i++)
{
for (int i = 0; i < n; i++) {
count += factorialRecur(n - 1);
}
return count;
}
[Test]
public void Test()
{
public void Test() {
// 可以修改 n 运行，体会一下各种复杂度的操作数量变化趋势
int n = 8;
Console.WriteLine("输入数据大小 n = " + n);