C Programming I made a program that works for this task Have

C++ Programming:

I made a program that works for this task:

Have a user input a string. Then display this string smashed up as follows: display the first character in the string, then the last, then the second, then the second to last, then the third... So if the string is “abcdef”, it will display: afbecd (input “abcdef”)\". And this is my coding for this task.

#include
#include

using namespace std;

void printLetters(string s);

int main()
{
   string seq;
   cout << \"Enter anything: \"<    getline(cin, seq);
   printLetters(seq);
   cout << endl;
  
   return 0;
}

void printLetters(string s)
{
   int a =s.length();
      
       if (a == 0)
       {
           return;
       }

   cout << s[0];
  
   if(a>1)
       cout<< s[a -1];
       s.erase(0, 1);
       a = s.length();

   if(a>=1)
       s.erase(a-1);
       printLetters(s);
}

If I run this programm, I get these answers:

Example 1:

Enter anything:

1234 (input)

1423 (output)

Example 2:

Enter anything:

12345678 (input)

18273645 (output)

Example 3:

Enter anything:

what does this sentence look like? (input)

w?heakti ld okeoso lt heicsn esten (output)

QUESTIOIN: Now, What I need to do is unmasing this program. Which means that If I enter my output that I got in the program above, I should get the input that i entered in the program.

And these are the examples that i should get.

Example 1:

Enter anything:

1423 (input)

1234 (output)

Example 2:

Enter anything:

w?heakti ld okeoso lt heicsn esten (input)

what does this sentence look like? (output)

Solution

#include <iostream>
#include <string>
using namespace std;
void printLetters(string s);
string unmash(string s);
int main()
{
string seq;
cout << \"Enter anything: \"< getline(cin, seq);
printLetters(seq);
cout << endl;
string unm = unmash(seq);
cout <<\"Unmashed:\"<< unm << endl;
  
return 0;
}
void printLetters(string s)
{
int a=s.length();
  
if (a == 0)
{
return;
}
cout << s[0];
  
if(a>1)
cout<< s[a -1];
s.erase(0, 1);
a = s.length();
if(a>=1)
s.erase(a-1);
printLetters(s);
}
string unmash(string s){
   int a = s.length();
   int i=0;
   string st = \"\";
   //add odd indexed
   while(i<a){
       st += s[i];
       i = i+2;
   }
   // check even or not.
   a%2==0?i=a+1:i=a;
  
   // add to string in reverse order.
   while(i>0){
       st += s[i];
       i = i-2;
   }
   return st;
}

/*
sample output
Enter anything: 1423
1342
Unmashed:1234
*/