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#include <iostream>
#include <string>
#include <fstream>
using namespace std;
short option = 3;
short method = 3;
int opt();
char key[54];
char lookup[53] = "abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ";
char enc(char c);
char dec(char c);
string phrase;
bool is_a_good(string & line);
bool init(const char beta, const string & text);
void condense(string & str);
void krypt();
int main()
{
opt();
start:
cout << "Enter a phrase containing all letters of the alphabet. \n(Each letter should appear only once.) "<< endl;
do{
//cin >> phrase;
getline(cin, phrase);
condense(phrase);
}while (!is_a_good(phrase));
cout << "phrase = " << phrase << " \n";
for (int i = 0; i < 27; ++i)
{
key[i] = phrase[i];
}
string s;
if (option == 0)
{
if (method == 0)
krypt();
else {
cout << "encrypt? " << endl; getline(cin, s);
for (int i = 0; i < s.length(); ++i)
{
s[i] = enc(s[i]);
}
cout << "ENCRYPTED: " << s << endl; }
}
if (option == 1)
{
if (method == 0)
krypt();
else {
cout << "decrypt? "; getline(cin, s);
for (int i = 0; i < s.length(); ++i)
{
s[i] = dec(s[i]);
}
cout << "DECRYPTED: " << s << endl; }
}
goto start;
}
int opt()
{
cout << "Encrypt or decrypt, 0 or 1? " << endl;
cin >> option; cin.ignore();
cout << "Krypt a file or krypt text from keyboard? 0 or 1\n";
cin >> method; cin.ignore();
return 0;
}
char enc(char c)
{
int index = 0; char letter;
if (isalpha(c))
{
if (!isalpha(c))
c = tolower(c);
//c = tolower(c);
while (c != lookup[index])
{
++index;
}
c = key[index];
}
letter = c;
return letter;
}
char dec(char c)
{
int index = 0; char letter;
if (isalpha(c))
{
//c = tolower(c);
if (!isalpha(c))
c = tolower(c);
while (c != key[index])
{
++index;
}
c = lookup[index];
}
letter = c;
return letter;
}
bool is_a_good(string & line)
{
short time = 0;
short testsize = 26;
if (method == 0)
testsize *= 2;
bool ok = true;
char alpha = 'a';//testing
if (line.length() != testsize)
{//cout << "wrong sizE! "<< endl;
return !ok;}
for (int i = 0; i < line.length(); ++i)
{
++time;
if (time == 27)
alpha = 'A';
//if (method != 0)
// line[i] = tolower(line[i]);
if (!isalpha(line[i]))
line[i] = tolower(line[i]);
if (!init(alpha, line))
{
cout << "alpha = " << alpha << " " << endl;
cout << "time = " << time << endl;
return !ok;}
++alpha;
//cout << "alpha = " << alpha << " \n" << endl;
}
return true;
}
bool init(const char beta, const string & text)
{
bool good = false;
for (int i = 0; i < text.length(); ++i)
{
if (text[i] == beta)
return true;
}
return false;
}
void condense(string & str)
{
string newstr = str;
string temp = "";
cout << "first str = " << str << " \n";
char t;
for (int i = 0; i < newstr.length(); ++i)
{
t = newstr[i];
if (!init(t, temp) )
if (isalpha(t))
temp += t;
}
str = temp;
cout << "str = " << str << " \n" << endl << " \n";
return;
}
void krypt()
{
string s;
char l;
ifstream fin;
ofstream fout;
ifstream tin;
string sin, sout;
cout << "krypt which file? \n";
cin >> sin;
cout << "save it to .... \n";
cin >> sout;
tin.open(sin.c_str(), ios::binary);
if (!tin.is_open())
{cout << sin << " does not exist. " << endl; exit(1); }
tin.close();
tin.open(sout.c_str(), ios::binary);
if (tin.is_open())
{ cout << sout << " already exists. " << endl; exit(1); }
tin.close();
//cout << "hey you guys!!!" << endl;
fin.open(sin.c_str(), ios::binary);
fout.open(sout.c_str(), ios::binary);
if (option == 0 )
{
do{
//getline(fin, s);
fin.get(l);
if (fin.eof())
break;
//s[i] = enc(s[i]);
//if (isalpha(l))//testing
l = enc(l);
fout.put(l);
}while (!fin.eof() );
}
else if (option == 1 )
{
do{
fin.get(l);
if (fin.eof())
break;
//if (isalpha(l))//testing
l = dec(l);
fout.put(l);
}while (!fin.eof() );
}
else cout << "invalid selection. \n";
return;
}
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