Hjælp til forklaring

Hejsa eksperten

Er der nogen der gider sætte nogle forklaringer ind til denne kode?

#include <iostream>
#include <string>
#include <cstdlib>
#include <fstream>


using namespace std;

char ae=-111, oe=-101, aa=134;

string Crypt(const string& aIn)
{
  static const char Arr1[] = "klmnopqrstuvwxyzabcdefghij";
  static const char Arr2[] = "KLMNOPQRSTUVWXYZABCDEFGHIJ";
  int idx;
  string Out;
  for(idx = 0; idx < aIn.size(); idx++)
  {
      int ii = aIn[idx] - 'a';
      int jj = aIn[idx] - 'A';
      if(aIn[idx] >= 'a' && aIn[idx] <= 'z')
        Out += Arr1[ii];
      else if(aIn[idx] >= 'A' && aIn[idx] <= 'Z')
        Out += Arr2[jj];
      else
        Out += aIn[idx];
  }
  return Out;
}
string Decrypt(const string& aIn)
{
  static const char Arr1[] = "qrstuvwxyzabcdefghijklmnop ";
  static const char Arr2[] = "QRSTUVWXYZABCDEFGHIJKLMNOP ";
  int idx;
  string Out;
  for(idx = 0; idx < aIn.size(); idx++)
  {
      int ii = aIn[idx] - 'a';
      int jj = aIn[idx] - 'A';
      if(aIn[idx] >= 'a' && aIn[idx] <= 'z')
        Out += Arr1[ii];
      else if(aIn[idx] >= 'A' && aIn[idx] <= 'Z')
        Out += Arr2[jj];
      else
        Out += aIn[idx];
  }
  return Out;
}

int main()
{
  string Line, dummy, Crypted, Decrypted;
  int x;
  cout << "hvad "<<oe<<"nsker du at g"<<oe<<"re:" << endl;
  cout << "1: Kryptere" << endl;
  cout << "2: Dekryptere" << endl;
  cout << "Valg: ";
  cin >> x;
  cout << "Skriv noget: ";
    cout.flush();
  getline (cin, dummy);
  getline(cin, Line);
  switch (x) {
  case 1:
        Crypted = Crypt(Line);       
        cout << "Krypteret: " << Crypted << endl;
        break;
  case 2:
        Decrypted = Decrypt(Line);
        cout << "Dekrypteret: " << Decrypted << endl;
        break;
  default:
        cout << "du skal v"<<ae<<"lge 1 eller 2." << endl;       
        main();
     
  }
  system("pause");
}

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