func_code_string: #include <bits/stdc++.h>   using namespace std;   const int INF = 1000000001;   template <class T, class U>   ostream &operator<<(ostream &out, const pair<T, U> &p) {     return out << p.first <<     << p.second;   }   template <class T>   ostream &operator<<(ostream &out, const vector<T> &v) {     for (typeof((v).begin()) i = ((v).begin()); i != (v).end(); ++i) {       out << *i <<    ;     }     return out;   }   template <class T, class U>   istream &operator>>(istream &in, pair<T, U> &p) {     return in >> p.first >> p.second;   }   template <class T>   istream &operator>>(istream &in, vector<T> &v) {     for (typeof((v).begin()) i = ((v).begin()); i != (v).end(); ++i) {       in >> (*i);     }     return in;   }   template <class T>   ostream &operator,(ostream &out, const T &t) {     return out << t;   }   template <class T>   istream &operator,(istream &in, T &t) {     return in >> t;   }   int io_init() {     ios_base::sync_with_stdio(false);     cin.tie(0);     cout.tie(0);     cout, fixed, setprecision(9);     return 1;   }   int _io_dummy = io_init();   template <class T, class U>   bool remin(T &a, const U &b) {     return b < a ? a = b, true : false;   }   template <class T, class U>   bool remax(T &a, const U &b) {     return b > a ? a = b, true : false;   }   const int N = 1000000;   int D[N];   void calcPrimes(int n = N) {     for (int i = 2; i * i < n; ++i) {       if (D[i]) {         continue;       }       for (int j = i * i; j < n; j += i) {         D[j] = i;       }     }   }   bool isPrime(int x) { return x > 1 && D[x] == 0; }   int rev(int x) {     ostringstream oss;     oss, x;     string s = oss.str();     reverse((s).begin(), (s).end());     istringstream iss(s);     iss, x;     return x;   }   int main() {     calcPrimes();     string s =          qd ucyhf yi q fhycu dkcruh mxeiu huluhiu yi q tyvvuhudj fhycu dkcruh.            oekh jqia yi je vydt jxu djx ucyhf. n ;     s +=  jxu ydfkj sediyiji ev q iydwbu ydjuwuh d (1 <= d <= 11184) - jxu             edu-rqiut ydtun ev jxu ucyhf je vydt n ;     s +=  ekjfkj q iydwbu dkcruh. ;     for (int i = 0; i < (10); ++i) {       for (typeof((s).begin()) c = ((s).begin()); c != (s).end(); ++c) {         if (!isalpha(*c)) continue;         if ((*c)++ ==  z ) *c =  a ;       }     }     cerr, s,   n ;     int x;     cin, x;     int n = 0, r;     for (int i = 13; i < N; i += 2) {       if (isPrime(i) && (r = rev(i)) != i && isPrime(r)) {         ++n;         if (n == x) {           cout, i,   n ;           break;         }       }     }   }   