#include <bits/stdc++.h>
using namespace std;
// Function for encryption
string encrypted_string(string strg)
{
string EncryptedString = { strg[0] };
for (int t = 1; t < strg.length(); t++) {
if (t % 2 == 1) {
EncryptedString.push_back(
strg[t]); // At odd position, append the
// next character
}
else {
EncryptedString.insert(
0, 1, strg[t]); // At Even position, prepend
// the next character
}
}
// print the resultant string
return EncryptedString;
}
// Function for decryption
string decrypted_string(string strg)
{
// Check the divisibility of length of string by 2
if (strg.length() % 2 != 0) {
string DecryptedString = { strg[0] };
for (int t = 1; t < strg.length(); t++) {
DecryptedString.push_back(
strg[strg.length() - 1
- t]); // First add the characters from
// the back
DecryptedString.push_back(
strg[t]); // from the front
}
reverse(
DecryptedString.begin(),
DecryptedString.end()); // Reverse the final
// string to get output
return DecryptedString;
}
else {
string reverse_strg = strg;
reverse(
reverse_strg.begin(),
reverse_strg
.end()); // In case of even length, reverse
// the given string first
string DecryptedString = { reverse_strg[0] };
// Looping over the reversed string
for (int t = 1; t < reverse_strg.length(); t++) {
DecryptedString.push_back(
reverse_strg[reverse_strg.length() - 1
- t]); // First add the
// characters from the
// back
DecryptedString.push_back(
reverse_strg[t]); // and then from the front
}
reverse(
DecryptedString.begin(),
DecryptedString.end()); // Reverse the final
// string to get output
return DecryptedString;
}
}
// Testing the algorithm with Driver Code
int main()
{
cout << encrypted_string("geeks") << endl;
cout << encrypted_string("geeksforgeeks") << endl;
cout << encrypted_string("strive") << endl;
cout << encrypted_string("vikaschitturi") << endl;
cout << encrypted_string("padmachitturi") << endl;
cout << encrypted_string("hackerrank") << endl;
cout << encrypted_string("hackerearth") << endl;
cout << encrypted_string("codechef") << endl;
cout << encrypted_string("IamVikas") << endl;
cout << encrypted_string("HelloHowareyou") << endl;
cout << encrypted_string("whatareyoudoing") << endl;
cout << decrypted_string("segek") << endl;
cout << decrypted_string("segosegekfrek") << endl;
cout << decrypted_string("vrstie") << endl;
cout << decrypted_string("iuthskviacitr") << endl;
cout << decrypted_string("iuthadpamcitr") << endl;
cout << decrypted_string("nrechakrak") << endl;
cout << decrypted_string("hreechakrat") << endl;
cout << decrypted_string(encrypted_string("IamVikas"))
<< endl;
cout << decrypted_string(
encrypted_string("HelloHowareyou"))
<< endl;
return 0;
}
