Level 1 finished

C语言学习笔记.md

@@ -2,4 +2,32 @@
 
 # 记录你学习过程中的所见所思！酸甜苦辣！
 
-# 看什么看！ 赶紧填坑啊！ 
+# 看什么看！ 赶紧填坑啊！ 
+git{
+有3级：
+  1.working folder 工作区
+  2.stage 
+  3.版本管理仓库
+git add添加的是变化
+git commit 是将stage中的变化增加到仓库
+git push 将仓库推到远端
+git clone和git pull：https://www.jianshu.com/p/c6a0397ec6f5
+}
+cin执行被跳过：https://blog.csdn.net/weixin_48066554/article/details/106825215
+console控制台相关：https://www.cnblogs.com/flowingwind/p/8159035.html
+{
+  注意算术移位和逻辑移位
+  有关补码、原码、反码：https://www.cnblogs.com/dongao/p/11538424.html
+
+}
+
+记录一些已写的函数：
+需要头文件<string>
+其中s为打开文件的类型
+FILE *getfile(string s)
+{
+  cout << "please put in the path" << endl;
+  string path;
+  cin >> path;
+  return fopen(path.c_str(), s.c_str());
+}

level1/p01_runningLetter/runningLetter.cpp

@@ -0,0 +1,29 @@
+#define WIDTH 60
+#include <iostream>
+#include <string>
+#include <Windows.h>
+#include <stdio.h>
+using namespace std;
+int main()
+{
+  system("mode con cols=60 lines=1");
+  char c;
+  string s;
+  int n = 0, x = 0;
+  cin >> s;
+  int len = s.length();
+  while (true)
+  {
+    system("mode con cols=60 lines=1");
+    for (int i = 0; i < n; i++)
+    {
+      cout << ' ';
+    }
+    cout << s;
+    Sleep(50);
+    system("cls");
+    x = (x + 1) % (2 * (WIDTH - len));
+    n = (WIDTH - len - abs(x - WIDTH + len));
+  }
+  return 0;
+}

level1/p02_isPrime/source.cpp

@@ -0,0 +1,35 @@
+#define WIDTH 60
+#include <iostream>
+#include <string>
+#include <Windows.h>
+#include <math.h>
+#include <stdio.h>
+using namespace std;
+bool judge(int n)
+{
+  if (n < 2)
+  {
+    return false;
+  }
+  for (int i = 2; i <= sqrt(n); i++)
+  {
+    if (n % i == 0)
+      return false;
+  }
+  return false;
+}
+int main()
+{
+  int x;
+  cin >> x;
+  if (judge(x))
+  {
+    cout << "yes";
+  }
+  else
+  {
+    cout << "no" << endl;
+  }
+  system("pause");
+  return 0;
+}

level1/p03_Diophantus/source.cpp

@@ -0,0 +1,9 @@
+#include<iostream>
+#include<math.h>
+#include<stdio.h>
+using namespace std;
+int main() {
+  cout <<(5+4)/(1-1.0/6-1.0/12-1.0/7-1.0/2)-4 <<endl;
+  system("pause");
+	return 0;
+}

level1/p04_ narcissus/source.cpp

@@ -0,0 +1,22 @@
+#include <iostream>
+#include <math.h>
+#include <stdio.h>
+using namespace std;
+bool judge(int n)
+{
+  if (pow(n / 100, 3) + pow(n / 10 % 10, 3) + pow(n % 10, 3) == n)
+  {
+    return true;
+  }
+  return false;
+}
+int main()
+{
+  for (int i = 100; i <= 999; i++)
+  {
+    if (judge(i))
+      cout << i << endl;
+  }
+  system("pause");
+  return 0;
+}

level1/p05_allPrimes/source.cpp

@@ -0,0 +1,42 @@
+#include <iostream>
+#include <math.h>
+#include <stdio.h>
+#include <Windows.h>
+#include <time.h>
+using namespace std;
+int primes[170], pn = 1;
+bool judge(int n)
+{
+  if (n < 2)
+    return false;
+  for (int i = 0; i < pn; i++)
+  {
+    if (n % primes[i] == 0)
+      return false;
+    if (primes[i] > sqrt(n))
+      return true;
+  }
+  return false;
+}
+int main()
+{
+  primes[0] = 2;
+  DWORD start_time = GetTickCount();
+  int start_clock = clock();
+  cout << 2 << endl;
+  for (int i = 3; i <= 1000; i = i + 2)
+  {
+    if (judge(i))
+    {
+      cout << i << endl;
+      primes[pn] = i;
+      pn = pn + 1;
+    }
+  }
+  DWORD end_time = GetTickCount();
+  int end_clock = clock();
+  cout << "time:" << end_time - start_time << endl;
+  cout << "clock:" << end_clock - start_clock << endl;
+  system("pause");
+  return 0;
+}

level1/p06_Goldbach/source.cpp

@@ -0,0 +1,35 @@
+#include <iostream>
+#include <math.h>
+#include <stdio.h>
+#include <Windows.h>
+#include <time.h>
+using namespace std;
+bool judge(int n)
+{
+  if (n < 2)
+  {
+    return false;
+  }
+  for (int i = 2; i <= sqrt(n); i++)
+  {
+    if (n % i == 0)
+    {
+      return false;
+    }
+  }
+  return true;
+}
+int main()
+{
+  for (int i = 4; i <= 100; i = i + 2)
+  {
+    for (int j = 2; j < 100; j++)
+      if (judge(j) && judge(i - j))
+      {
+        cout << i << "=" << j << "+" << i - j << endl;
+        break;
+      }
+  }
+  system("pause");
+  return 0;
+}

level1/p07_encrypt_decrypt/README.md

@@ -1,3 +1,7 @@
 ### 功能要求：
 
-1. 分别编写“加密”、“解密”函数，输入为任意长度的字符串
+1. 分别编写“加密”、“解密”函数，输入为任意长度的字符串
+
+注意：只针对小写字母进行加密
+加密方法：记录小写字母的数据可用5位二进制表示，在末尾添一位随机数，然后分成三个二位，再和下一个(首尾相连)字母的前两位合并成一个四位二进制数，再在末尾添一位随机数，生成一个新的字符。
+

level1/p07_encrypt_decrypt/source.cpp

@@ -0,0 +1,79 @@
+#include <iostream>
+#include <math.h>
+#include <stdio.h>
+#include <Windows.h>
+#include <string>
+#include <time.h>
+using namespace std;
+int group[1000][4];
+int input[1000][3];
+void decrypt()
+{
+  string s;
+  cout << "please put in the contents you want to decrypt" << endl;
+  cin >> s;
+  unsigned j = 0;
+  unsigned len = s.length();
+  for (unsigned i = 0; i < len; i = i + 3)
+  {
+    char a = ((s[i] - 97) / 8) * 8 + ((s[i + 1] - 97) / 8) * 2 + ((s[i + 2] - 97) / 8) / 2 + 97;
+    cout << a;
+  }
+
+  cout << endl;
+}
+void encrypt()
+{
+  srand(time(0));
+  string s;
+  cout << "please put in the contents you want to encrypt" << endl;
+  cin >> s;
+  unsigned len = s.length();
+  for (unsigned i = 0; i < len; i++)
+  {
+    srand((unsigned)time(NULL));
+    input[i][0] = (s[i] - 97) / 8;
+    input[i][1] = ((s[i] - 97) / 2) % 4;
+    input[i][2] = ((s[i] - 97) % 2) * 2 + rand() % 2;
+  }
+  for (unsigned i = 0; i < len; i = i + 1)
+  {
+    srand((unsigned)time(NULL));
+    char a = input[i][0] * 8 + input[(i + 1) % len][0] * 2 + rand() % 2 + 97;
+    char b = input[i][1] * 8 + input[(i + 1) % len][1] * 2 + rand() % 2 + 97;
+    char c = input[i][2] * 8 + input[(i + 1) % len][2] * 2 + rand() % 2 + 97;
+
+    cout << a;
+    cout << b;
+    cout << c;
+  }
+  cout << endl;
+  system("pause");
+}
+int main()
+{
+  cout << "encrypt or decrypt?" << endl
+       << "please put in E or D to choose the mode or put in e to exit the program" << endl;
+  char c;
+  cin >> c;
+  switch (c)
+  {
+  case 'E':
+  {
+    encrypt();
+    break;
+  }
+  case 'D':
+  {
+    decrypt();
+    break;
+  }
+  case 'e':
+    break;
+  default:
+    cout << "??????????????????????" << endl
+         << "Please check!";
+  }
+  system("pause");
+  return 0;
+}

level1/p08_hanoi/source.cpp

@@ -0,0 +1,25 @@
+#include <iostream>
+#include <math.h>
+#include <stdio.h>
+#include <Windows.h>
+#include <time.h>
+using namespace std;
+int hanoi(int n, int from, int goal, int temp)
+{
+  if (n != 1)
+  {
+    int a = hanoi(n - 1, from, temp, goal) + hanoi(1, from, goal, temp) + hanoi(n - 1, temp, goal, from) + 1;
+    return a;
+  }
+  else
+    cout << (char)(from + 65) << "->" << (char)(goal + 65) << endl;
+  return 1;
+}
+int main()
+{
+  int n;
+  cin >> n;
+  cout << hanoi(n, 0, 2, 1) << endl;
+  system("pause");
+  return 0;
+}