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#include <stdio.h>
#include <stdlib.h>
#define LL long long
#define BIGMOD 1000012177LL
#define DNUM 31LL

#define DBG(X)

bool check_palindrome_L(int n) {
  DBG(printf("check palindromeL %d\n", n));
  int i=0;
  LL ph = 0;
  LL hash = 1;
  for (i=0; i < n/2; i++) {
    LL c = getchar() - 'a';
    DBG(printf("c: %lld\n", c));
    ph =  (ph + (c * hash)) % BIGMOD;
    hash = (hash * DNUM) % BIGMOD;
  }
  if (n%2 == 1) {
    char c = getchar();
    DBG(printf("ignoring char %c as it is in the middle\n", c));
  }
  else {
    DBG(printf("reached half...\n"));
  }

  i = 0;
  LL sh = 0; // suffix hash
  for (i=0; i < n/2; i++) {
    LL c = getchar() - 'a';
    DBG(printf("c: %lld\n", c));
    sh = (DNUM * sh + c) % BIGMOD;
  }

  DBG(printf("ph=%lld, sh=%lld\n", ph, sh));
  return ph == sh;
}

struct Packed16Chars {
  unsigned int c0:5,c1:5,c2:5,c3:5,c4:5,c5:5,c6:5,c7:5,c8:5,c9:5,c10:5,c11:5,c12:5,c13:5,c14:5,c15:5;
} __attribute__((packed));

class RollingWindow {
   int start_;
   int end_;
   int correspondingStartRealIdx_;
   int maxLength_;
   bool overflow_;
public:
   RollingWindow(int maxLength) {
       start_ = 0;
       end_ = 0;
       correspondingStartRealIdx_ = 0;
       maxLength_ = maxLength;
       overflow_ = false;
       DBG(printf("Creating rolling window of size: %d\n", maxLength));
   }

   void move1() {
       end_++;
       if (end_ == maxLength_) {
           overflow_ = true;
           end_ = 0;
           start_ = 1;
           correspondingStartRealIdx_++;
       } else if (overflow_) {
           start_++;
           correspondingStartRealIdx_++;
           if (start_ > maxLength_) {
               start_ = 0;
           }
       }
   }

   int translateRealIdx(int realIdx) {
       int translatedRealIdx = realIdx - correspondingStartRealIdx_;
       if (translatedRealIdx < 0) {
           fprintf( stderr, "ERROR translated real index <0\n");
           return -1;
       }
       // must be within [0, maxLength_)
       translatedRealIdx += start_;
       translatedRealIdx %= maxLength_;
       //DBG(printf("translateRealIdx(%d) -> %d\n", realIdx, translatedRealIdx));
       return translatedRealIdx;
   }
};

void selftest_rw() {
    RollingWindow* rw = new RollingWindow(7);
    for (int i=0; i < 31; i++) {
        printf("selftest rw[%d]=%d\n", i, rw->translateRealIdx(i));
        rw->move1();
    }
    for (int i=0; i < 31; i++) {
        printf("selftest2 rw[%d]=%d\n", i, rw->translateRealIdx(i));
    }
}

class StreamBuf {
  int chunksCount_;
  int chunkLength_ = 8192;
  int chunkLength16_;
  int bufLength_;
  int bufLength16_;

  Packed16Chars** buf_;

  int realLength_ = 0;
  RollingWindow* rw;

public:
  StreamBuf(int maxLength) {
    DBG(printf("sizeof(Packed16Chars)=%d\n", sizeof(Packed16Chars)));
    bufLength_ = (maxLength / 16) + 100;
    bufLength16_ = maxLength;
    chunksCount_ = (bufLength_  / chunkLength_) + 1 ;
    chunkLength16_ = chunkLength_ * 16;
    buf_ = new Packed16Chars*[chunksCount_];
    for (int i=0; i < chunksCount_; i++) {
        buf_[i] = (Packed16Chars*)malloc(chunkLength_ * sizeof(Packed16Chars));
        DBG(printf("Allocated [%d] %d bytes at %x\n", i, chunkLength_ * sizeof(Packed16Chars), buf_[i]));
        if (!buf_[i]) {
          chunksCount_ = i;
          break;
        }
    }
    rw = new RollingWindow(chunkLength16_ * chunksCount_);
    DBG(printf("mem usage: %d bytes (%f MB)", bufLength_ * sizeof(Packed16Chars),
        1.0 * bufLength_*sizeof(Packed16Chars) / (1024 * 1024)));
  }

  void add(unsigned char c) {
    // DBG(printf("stream add(%d)\n", c));
    internal_place(rw->translateRealIdx(realLength_), c);
    rw->move1();
    ++realLength_;
  }

  void fakeAdd(unsigned char c) {
    ++realLength_;
  }

  int getRealLength() {
    return realLength_;
  }

  unsigned char get(int realIdx) {
    int translatedRealIdx = rw->translateRealIdx(realIdx);
    int chunkIdx, withinChunkIdx, subIdx;
    to_subidx(translatedRealIdx, &chunkIdx, &withinChunkIdx, &subIdx);

    Packed16Chars &p = buf_[chunkIdx][withinChunkIdx];
    switch (subIdx) {
      case 0: return p.c0;
      case 1: return p.c1;
      case 2: return p.c2;
      case 3: return p.c3;
      case 4: return p.c4;
      case 5: return p.c5;
      case 6: return p.c6;
      case 7: return p.c7;
      case 8: return p.c8;
      case 9: return p.c9;
      case 10: return p.c10;
      case 11: return p.c11;
      case 12: return p.c12;
      case 13: return p.c13;
      case 14: return p.c14;
      case 15: return p.c15;
    }
    return -1;
  }

  void print() {
    for (int jj=0; jj < realLength_; jj++) {
      printf("%d ", get(jj));
    }
    printf("\n");
  }

private:
  void to_subidx(int idx, int* chunk, int* withinChunkIdx, int* subIdx) {
      *chunk = idx / chunkLength16_;
      int withinChunkIdx16 = idx % chunkLength16_;
      *withinChunkIdx = withinChunkIdx16 / 16;
      *subIdx = withinChunkIdx16 % 16;
      return;
  }

  void internal_place(int idx, char c) {
    int chunkIdx, withinChunkIdx, subIdx;
    to_subidx(idx, &chunkIdx, &withinChunkIdx, &subIdx);

    Packed16Chars &p = buf_[chunkIdx][withinChunkIdx];
    switch (subIdx) {
      case 0: p.c0 = c; break;
      case 1: p.c1 = c; break;
      case 2: p.c2 = c; break;
      case 3: p.c3 = c; break;
      case 4: p.c4 = c; break;
      case 5: p.c5 = c; break;
      case 6: p.c6 = c; break;
      case 7: p.c7 = c; break;
      case 8: p.c8 = c; break;
      case 9: p.c9 = c; break;
      case 10: p.c10 = c; break;
      case 11: p.c11 = c; break;
      case 12: p.c12 = c; break;
      case 13: p.c13 = c; break;
      case 14: p.c14 = c; break;
      case 15: p.c15 = c; break;
    }
  }
};

bool check_palindrom_stream(int maxLength) {
  // we need maxLength/4 most recent characters to keep
  StreamBuf stream((maxLength+3)/4);

  char c = getchar() - 'a';
  LL ph = c % BIGMOD;
  stream.add(c);

  c = getchar();
  if (c < 'a' || c > 'z') {
    return true;
  }
  c -= 'a';
  LL sh = c % BIGMOD;
  stream.add(c);

  LL hh = 1;

  bool is_palindrome_now;

  LL i = 1;
  while (true) {
    is_palindrome_now = sh == ph;
    c = getchar();
    if (c < 'a' || c > 'z') {
      break;
    }
    c -= 'a';
    if (i > (maxLength + 3) / 2) {
      stream.fakeAdd(c);
    } else {
      stream.add(c);
    }
    if (c < 0) printf("ERROR!\n");
    // If i is even (next i is odd)
    if (i%2 == 0)
    {
         // Add next character after first half at beginning
         // of 'ph'
         hh = (hh*DNUM) % BIGMOD;
         ph  = (ph + hh*stream.get(i/2))%BIGMOD;

         // Add next character after second half at the end
         // of second half.
         sh = (sh*DNUM + c)%BIGMOD;
    }
    else
    {
         // If next i is odd (next i is even) then we
         // need not to change firstr, we need to remove
         // first character of second and append a
         // character to it.
         sh = DNUM*(sh + BIGMOD - (stream.get((i+1)/2)*hh)%BIGMOD)%BIGMOD;
         sh = (sh + c) % BIGMOD;
    }
    DBG(printf("c=%d ph=%lld, sh=%lld\n", c, ph, sh));
    i++;

    DBG(stream.print());
  }

  return is_palindrome_now;
}

int main() {
  // selftest_rw();

  int n;
  scanf("%d\n", &n);
  bool is_palindrome = false;
  if (n == 0) {
    is_palindrome = check_palindrom_stream(20000000);
  } else {
    is_palindrome = check_palindrome_L(n);
  }
  printf("%s\n", is_palindrome ? "TAK" : "NIE");

  return 0;
}