encode/decode
i would like to swap letters of the input message to a key that i have below and reverse for the decode
a=n
b=o
c=p
d=q
e=r
f=s
g=t
h=u
i=v
j=w
k=x
l=y
m=z
so if i put in "hi how are you"
it outputs
"uv ubj ner lbh"
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
|
#include <iostream>
#include <string>
using namespace std;
int main()
{
string code;
string message;
while (true)
{
cout << "encode or decode: ";
cin >> code;
if (code == "encode")
{
cout << "Input the message would u like to encode" << endl;
getline(cin >> ws, message);
cout << message << endl;
}
else if (code == "decode")
{
cout << "Input the message would u like to decode" << endl;
cin >> message;
}
else
{
cout << "thats is none of the choices please try again" << endl;
continue;
}
return 0;
}
}
|
Have you used
std::map before? You could map the keys to the a values. Another approach would be something like:
1
2
3
4
5
6
|
std::string alphabets[] = {"abc...", "nopq..."};
//encrypting:
iterator over message
message[i] = alphabets[1][i];
|
Though, you are shifting by 13 to the right each time. So you could even do something like:
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
|
#include <iostream>
#include <string>
#include <algorithm>
#include <cctype>
int main()
{
std::string message = "hi how are you";
std::cout << "Message : " << message << std::endl;
std::transform(message.begin(), message.end(), message.begin(), [](int c){ if(isalpha(c) && (c=tolower(c)) && (c+= 13) && c > 'z') c -= 26; return c;});
std::cout << "Encrypted: " << message << std::endl;
std::transform(message.begin(), message.end(), message.begin(), [](int c){ if(isalpha(c) && (c=tolower(c)) && (c-= 13) && c < 'a') c += 26; return c;});
std::cout << "Decrypted: " << message << std::endl;
}
|
Message : hi how are you
Encrypted: uv ubj ner lbh
Decrypted: hi how are you |
You can use functions/for loop instead of
std::transform
i want to be able to input the message every time
i got it
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
|
#include <iostream>
#include <string>
#include <algorithm>
#include <cctype>
using namespace std;
int main()
{
string code;
string message;
while (true)
{
cout << "encode or decode: ";
cin >> code;
if (code == "encode")
{
cout << "Input the message would u like to encode" << endl;
getline(cin >> ws, message);
transform(message.begin(), message.end(), message.begin(), [](int c){ if (isalpha(c) && (c = tolower(c)) && (c += 13) && c > 'z') c -= 26; return c; });
cout << message << endl;
}
else if (code == "decode")
{
cout << "Input the message would u like to decode" << endl;
getline(cin >> ws, message);
transform(message.begin(), message.end(), message.begin(), [](int c){ if (isalpha(c) && (c = tolower(c)) && (c -= 13) && c < 'a') c += 26; return c; });
cout << message << endl;
}
else
{
cout << "Sorry, that is none of the choices please try again" << endl;
continue;
}
return 0;
}
}
|
Topic archived. No new replies allowed.