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#include <cstdio>
#include <cmath>
#include <iostream>
#include <algorithm>
#include <queue>
#include <list>
#include <vector>
#include <map>
#include <set>
#include <string>
#include <cstring>
#include <cassert>
#include <limits.h>

using namespace std;

#define ST first
#define ND second
#define MP make_pair
#define PB push_back

#define REP(i,n) for(int i=0;i<(n);i++)
#define FOR(i,a,b) for(VAR(i,a);i<=(b);++i)
#define FORD(i,a,b) for(VAR(i,a);i>=(b);--i)
#define FORE(a,b) for(VAR(a,(b).begin());a!=(b).end();++a)
#define VAR(a,b) __typeof(b) a=(b)
#define SIZE(a) ((int)((a).size()))
#define ALL(x) (x).begin(),(x).end()
#define CLR(x,a) memset(x,a,sizeof(x))
#define ZERO(x) memset(x,0,sizeof(x))
#define S(t,i) scanf("%" ## t, &i)
#define SI(i) scanf("%d", &i)

const int MAXN=600000;
const unsigned int PRIME=2149840313;
const int BASE=26;
unsigned int p[MAXN];
const int MAXB = 16384;
char b[MAXB];
int n;

bool brute(char * b, int n) {
    REP(bi, n/2) {
        if (b[bi] != b[n-bi-1]) {
            printf("NIE\n");
            return false;
        }
    }
    return true;
}
int readChunk(char *b, int chunkSize) {
    int readSize = (int) fread(b, 1, chunkSize, stdin);
    while (readSize>0 && (b[readSize-1]<'a' || b[readSize-1]>'z')) {
        readSize--;
    }
    return readSize;
}
unsigned long long int pow(int base, int exp) {
    unsigned long long int result = 1;
    REP(i, exp) {
        result = result*base % PRIME;
    }
    return result;
}

int main() {
    ios_base::sync_with_stdio(0);
    
    scanf("%d ", &n);
    if (n) {
        if (n <= 2*MAXN+1) {
            char * pc = (char *) p;
            int readSize = 0;
            while (readSize < n/2) {
                readSize += fread(pc + readSize, 1, min(n/2-readSize, MAXB), stdin);
            }
            if (n & 1) {
                fread(b, 1, 1, stdin);
            }
            int pi = n/2;
            while (pi) {
                unsigned long bl = fread(b, 1, min(pi, MAXB), stdin);
                REP(bi, bl) {
                    if (pc[--pi] != b[bi]) {
                        printf("NIE\n");
                        return 0;
                    }
                }
            }
        } else {
            int half = n/2;
            int stride = (half+MAXN-1)/MAXN;
            int pi = 0;
            unsigned long long int h;
            while ((pi + 1) * stride < half) {
                fread(b, 1, stride, stdin);
                h = 0;
                REP(bi, stride) {
                    h = (h*BASE + (b[bi] - 'a')) % PRIME;
                }
                p[pi] = (unsigned int) h;
                pi++;
            }
            
            int center = 2*(half - pi*stride) + (n&1);
            fread(b, 1, center, stdin);
            if (!brute(b, center)) {
                return 0;
            }
            
            while (pi > 0) {
                fread(b, 1, stride, stdin);
                h = 0;
                long long int basePower = 1;
                REP(bi, stride) {
                    h = (h + (b[bi] - 'a') * basePower) % PRIME;
                    basePower = (basePower * BASE) % PRIME;
                }
                if (h != p[--pi]) {
                    printf("NIE\n");
                    return 0;
                }
            }
        }
    } else {
        unsigned int *p1 = p;
        unsigned int *p2 = p + MAXN/2;
        int stride1 = 67, stride2 = 68;
        int chunkSize = MAXB;
        int readSize = readChunk(b, chunkSize);
        if (feof(stdin)) {
            if (!brute(b, readSize)) {
                return 0;
            }
            printf("TAK\n");
            return 0;
        }
        unsigned long long int h1 = 0, h2 = 0;
        unsigned long long int basePower = 1;
        int pi1 = 0, pi2 = 0;
        while (readSize) {
            REP(bi, readSize) {
                char c = b[bi] - 'a';
                h1 = (h1*BASE + c) % PRIME;
                
                h2 = (h2 + c * basePower) % PRIME;
                basePower = (basePower * BASE) % PRIME;
                
                ++n;
                if (n % stride1 == 0) {
                    p1[pi1++] = (unsigned int) h1;
                    h1 = 0;
                }
                if (n % stride2 == 0) {
                    p2[pi2++] = (unsigned int) h2;
                }
            }
            readSize = readChunk(b, chunkSize);
        }
        int rest1 = n % stride1;
        if (rest1) {
            p1[pi1++] = (unsigned int) h1;
        } else {
            rest1 = stride1;
        }
        int rest2 = n % stride2;
        if (rest2) {
            p2[pi2++] = (unsigned int) h2;
        }
        
        unsigned long long int stridePow = pow(BASE, stride1);
        unsigned long long int x = pow(BASE, rest1);
        FORD(i, pi1-1, 1) {
            h1 = (p1[i] + x * p1[i-1]) % PRIME;
            p1[i-1] = (int) h1;
            x = x * stridePow % PRIME;
        }
        
        if (h1 != h2) {
            printf("NIE\n");
            return 0;
        }
        
        int i1 = rest1;
        int i2 = stride2;
        pi2 = 0;
        pi1--;
        while (i1<n && i2<n) {
            if (i1 == i2) {
                if (p1[pi1] != p2[pi2]) {
                    printf("NIE\n");
                    return 0;
                }
//                printf("%d %d\n", pi1, pi2);
                i1 += stride1;
                pi1--;
                i2 += stride2;
                pi2++;
            } else if (i1 < i2) {
                i1 += stride1;
                pi1--;
            } else {
                i2 += stride2;
                pi2++;
            }
            
        }
    }
    
    printf("TAK\n");
    return 0;
}