#include <library.h>

const string perm = "kjtembvwgcnqzalphyfoxurdis ";
const string alph = "abcdefghijklmnopqrstuvwxyz ";

int find(char c, string s, int pos)
{ if (pos >= s.length())
    return -1;
  else if (s[pos] == c)
    return pos;
  else
    return find(c, s, pos + 1); }

void translate(string text, string p, string a, int pos)
{ // print("pos = "); print(pos); new_line();
  // print("text = "); print(text); new_line();
  // print("text.length() = "); print((int)text.length()); new_line();

  if (pos >= text.length())
  { new_line();
    return; }
  const int where = find(text[pos], p, 0);
  if (where == -1)
    print("?");
  else
    print(a[where]);
  translate(text, p, a, pos + 1); }

void main()
{ print("encrypt (1) or decrypt (2) ? ");
  const int eord = read_int();
  read_line();              // to consume the \n I typed
  print("enter a line: ");
  const string text = read_line();
  if (eord == 1)
    translate(text, perm, alph, 0);
  else
    translate(text, alph, perm, 0); }