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/*
  Hashowanie napisow na podstawie rozwiazania zadania 
  Poszukiwania (autor Tomasz Czajka) z Potyczek Algorytmicznych 2015
  
*/

#include <cassert>
#include <iostream>
#include <limits>
#include <vector>
#include <cstring>
#include <cstdio>
#include <ctime>

using std::numeric_limits;
using std::vector;

typedef long long LL;
typedef unsigned long long ULL;

// Mersenne prime.
constexpr int primeExponent = 61;
constexpr ULL prime = (1ULL << primeExponent) - 1ULL;

// Modulo prime.
class Mod {
 public:
  // x must be < p
  explicit constexpr Mod(ULL x) : val{x} {}

  Mod operator+(Mod b) const {
    ULL res = val + b.val;
    if (res >= prime) res -= prime;
    return Mod{res};
  }

  Mod operator-(Mod b) const {
    ULL res = val;
    if (res < b.val) res += prime;
    res -= b.val;
    return Mod{res};
  }

  Mod operator*(unsigned b) const {
    unsigned a0 = unsigned(val);
    unsigned a1 = unsigned(val >> 32);
    ULL res0 = ULL(a0) * ULL(b);
    ULL res1 = ULL(a1) * ULL(b);
    ULL res =
      (res0 & prime) + (res0 >> primeExponent) +
      ((res1 << 32) & prime) + (res1 >> (primeExponent - 32));
    return Mod{res % prime};
  }

  Mod operator*(Mod b) const {
    unsigned a0 = unsigned(val);
    unsigned a1 = unsigned(val >> 32);
    unsigned b0 = unsigned(b.val);
    unsigned b1 = unsigned(b.val >> 32);
    ULL res0 = ULL(a0) * ULL(b0);
    ULL res1 = ULL(a0) * ULL(b1) + ULL(a1) * ULL(b0);
    ULL res2 = ULL(a1) * ULL(b1);
    ULL res =
      (res0 & prime) + (res0 >> primeExponent) +
      ((res1 << 32) & prime) + (res1 >> (primeExponent - 32)) +
      ((res2 << (64 - primeExponent)) & prime) +
      (res2 >> (2 * primeExponent - 64));
    return Mod{res % prime};
  }

  bool operator==(Mod b) const { return val == b.val; }

  void operator+=(Mod b) { *this = *this + b; }
  void operator-=(Mod b) { *this = *this - b; }
  void operator*=(unsigned b) { *this = *this * b; }
  void operator*=(Mod b) { *this = *this * b; }

  ULL Extract() const { return val; }

 private:
  ULL val;
};

Mod Power(Mod a, ULL n) {
  Mod res{1};
  ULL two_b = 1u;
  Mod a_two_b = a;
  while(two_b <= n) {
    if (n & two_b) res *= a_two_b;
    two_b <<= 1;
    a_two_b *= a_two_b;
  }
  return res;
}

template<ULL baseULL>
class Hash {
  static_assert(baseULL < prime, "base < prime");
  static constexpr Mod base = Mod{baseULL};

 public:
  Hash() : val{0}, powBaseLen{0} {}
  Hash(Mod v) : val{v}, powBaseLen{0} {}

  void Append(unsigned c) {
    val = val * base + Mod{c};
  }

  bool operator==(const Hash &b) const {
    return val == b.val;
  }

  Mod Extract() const { return val; }

 private:
  Mod val;
  Mod powBaseLen;
};


template<ULL baseULL> constexpr Mod Hash<baseULL>::base;

class StrongHash {
 public:
  StrongHash() : hash1{}, hash2{} {}
  StrongHash(Mod h1, Mod h2) : hash1{h1}, hash2{h2} {}

  void Append(unsigned c) {
    hash1.Append(c);
    hash2.Append(c);
  }

  bool operator==(const StrongHash &b) const {
    return hash1 == b.hash1 && hash2 == b.hash2;
  }

  Mod Extract1() const { return hash1.Extract(); }
  Mod Extract2() const { return hash2.Extract(); }

 private:
  Hash<1919222792405563639ULL> hash1;
  Hash<1940348388277362841ULL> hash2;
};


//-------------------------------------------------
template<ULL baseULL>
class HashRev {
  static_assert(baseULL < prime, "base < prime");
  static constexpr Mod base = Mod{baseULL};
  
 public:
  Mod revPow{0};
  HashRev() : val{0}, powBaseLen{1} {
  }
  HashRev(Mod v) : val{v}, powBaseLen{1} {
  }

  void Append(unsigned c) {
    Mod x = powBaseLen * Mod{c};
    val = val + x;
    powBaseLen = powBaseLen * base;
    
  }
  
  Mod Extract() const { return val; }

 private:
  Mod val;
  Mod powBaseLen;
};


template<ULL baseULL> constexpr Mod HashRev<baseULL>::base;
class StrongHashRev {
 public:
  StrongHashRev() : hash1{}, hash2{} {}
  StrongHashRev(Mod h1, Mod h2) : hash1{h1}, hash2{h2} {}

  void Append(unsigned c) {
    hash1.Append(c);
    hash2.Append(c);
  }

  Mod Extract1() const { return hash1.Extract(); }
  Mod Extract2() const { return hash2.Extract(); }

 private:
  HashRev<1919222792405563639ULL> hash1;
  HashRev<1940348388277362841ULL> hash2;
};

int main() {
  StrongHash sh;
  StrongHashRev shrev;
  int n;
  scanf("%d\n", &n);
  
  char c;
  
  while (c = getchar())
  {
    int x = c - 'a' + 1;
    if (x > 26 || x < 1) break;
    sh.Append(x);
    shrev.Append(x);
  }
  
  if (sh.Extract1() == shrev.Extract1() && sh.Extract2() == shrev.Extract2())
  {
    printf("TAK\n");
  }
  else
  {
    printf("NIE\n");
  }
  return 0;
}