#include <bits/stdc++.h>
using namespace std;
//#pragma GCC optimize("Ofast")
//#pragma GCC target("sse,sse2,sse3,ssse3,sse4,popcnt,abm,mmx,avx,tune=native")
 
#define ms(s, n) memset(s, n, sizeof(s))
#define FOR(i, a, b) for (int i = (a); i < (b); ++i)
#define FORd(i, a, b) for (int i = (a) - 1; i >= (b); --i)
#define FORall(it, a) for (__typeof((a).begin()) it = (a).begin(); it != (a).end(); it++)
#define sz(a) int((a).size())
#define present(t, x) (t.find(x) != t.end())
#define all(a) (a).begin(), (a).end()
#define uni(a) (a).erase(unique(all(a)), (a).end())
#define pb push_back
#define pf push_front
#define mp make_pair
#define fi first
#define se second
#define prec(n) fixed<<setprecision(n)
#define bit(n, i) (((n) >> (i)) & 1)
#define bitcount(n) __builtin_popcountll(n)
typedef long long ll;
typedef unsigned long long ull;
typedef long double ld;
typedef pair<int, int> pi;
typedef vector<int> vi;
typedef vector<pi> vii;
const int MOD = (int) 1e9 + 7;
const int FFTMOD = 119 << 23 | 1;
const int INF = (int) 1e9 + 23111992;
const ll LINF = (ll) 1e18 + 23111992;
const ld PI = acos((ld) -1);
const ld EPS = 1e-9;
inline ll gcd(ll a, ll b) {ll r; while (b) {r = a % b; a = b; b = r;} return a;}
inline ll lcm(ll a, ll b) {return a / gcd(a, b) * b;}
inline ll fpow(ll n, ll k, int p = MOD) {ll r = 1; for (; k; k >>= 1) {if (k & 1) r = r * n % p; n = n * n % p;} return r;}
template<class T> inline int chkmin(T& a, const T& val) {return val < a ? a = val, 1 : 0;}
template<class T> inline int chkmax(T& a, const T& val) {return a < val ? a = val, 1 : 0;}
inline ull isqrt(ull k) {ull r = sqrt(k) + 1; while (r * r > k) r--; return r;}
inline ll icbrt(ll k) {ll r = cbrt(k) + 1; while (r * r * r > k) r--; return r;}
inline void addmod(int& a, int val, int p = MOD) {if ((a = (a + val)) >= p) a -= p;}
inline void submod(int& a, int val, int p = MOD) {if ((a = (a - val)) < 0) a += p;}
inline int mult(int a, int b, int p = MOD) {return (ll) a * b % p;}
inline int inv(int a, int p = MOD) {return fpow(a, p - 2, p);}
inline int sign(ld x) {return x < -EPS ? -1 : x > +EPS;}
inline int sign(ld x, ld y) {return sign(x - y);}
mt19937 mt(chrono::high_resolution_clock::now().time_since_epoch().count());
inline int mrand() {return abs((int) mt());}
#define db(x) cerr << "[" << #x << ": " << (x) << "] ";
#define endln cerr << "\n";

struct SuffixArray {
    static const int maxn = 1e5 + 5;
    static const char sep = '$';

    int n;
    char s[maxn];
    int sa[maxn], ra[2][maxn];
    int lcp[maxn];

    void build(char* t) {
        strcpy(s, t), n = strlen(s);
        for (int i = 0; i < n; i++) {
            sa[i] = i, ra[0][i] = 0, ra[1][i] = s[i] + 1;
        }
        for (int d = 1; radixsort(); d <<= 1) {
            for (int i = 0; i < n; i++) {
                if (i + d < n) {
                    ra[1][i] = ra[0][i + d] + 1;
                }
                else {
                    ra[1][i] = 0;
                }
            }
        }
        buildlcp();
    }

    int radixsort() {
        static int p[maxn];
        static int tmpsa[maxn];
        static int tmpra[maxn];
        int mx = max(256, n) + 1;
        for (int step = 1; step >= 0; step--) {
            fill_n(p, mx, 0);
            for (int i = 0; i < n; i++) {
                p[ra[step][i] + 1]++;
                tmpsa[i] = sa[i];
            }
            partial_sum(p, p + mx, p);
            for (int i = 0; i < n; i++) {
                sa[p[ra[step][tmpsa[i]]]++] = tmpsa[i];
            }
        }
        int ptr = 0;
        tmpra[sa[0]] = ptr;
        for (int i = 1; i < n; i++) {
            int u = sa[i - 1];
            int v = sa[i];
            if (ra[0][u] < ra[0][v] || ra[1][u] < ra[1][v]) {
                ptr++;
            }
            tmpra[v] = ptr;
        }
        for (int i = 0; i < n; i++) ra[0][i] = tmpra[i];
        return ptr < n - 1;
    }

    void buildlcp() {
        for (int i = 0, k = 0; i < n; i++) {
            if (!ra[0][i]) lcp[ra[0][i]] = 0;
            else {
                for (int j = sa[ra[0][i] - 1]; s[i + k] == s[j + k] && s[i + k] != sep; k++);
                lcp[ra[0][i]] = k;
                k = max(k - 1, 0);
            }
        }
    }
} sa;

void solve() {
    int n, k; cin >> n >> k;
    string s; cin >> s;
    auto join = [&] (string s) {
        string t = s;
        reverse(all(t));
        return s + t;
    };
    auto ff = [&] (int d) {
        string t = s;
        reverse(all(t));
        string res = t.substr(0, d);
        res = join(s);
        res += t;
        return res;
    };
    //if (k == 2) {
    //    string res = s;
    //    FOR(d, 0, n + 1) {
    //        string t = join(s);
    //        t = t.substr(d, n);
    //        t = join(t);
    //        sa.build((char *) t.data());
    //        pi mn = mp(INF, INF);
    //        FOR(i, 0, n + 1) {
    //            chkmin(mn, mp(sa.ra[0][i], i));
    //        }
    //        chkmin(res, t.substr(mn.se, n));
    //    }
    //    cout << res << "\n";
    //    return;
    //}
    //if (k == 2) {
    //    string res = s;
    //    string mn = "";
    //    string t = join(s);
    //    FOR(i, 0, n) {
    //        chkmin(res, (s.substr(i) + mn).substr(0, n));
    //        if (mn == "" || ff(i) < mn) {
    //            mn = ff(i);
    //        }
    //    }
    //    cout << res << "\n";
    //    return;
    //}
    auto func = [&] (string s, int d) {
        s = join(s);
        s = s.substr(d, n);
        if (1 < k) {
            FOR(i, 1, min(k - 1, 15)) {
                s = join(s);
                int ptr = n;
                while (ptr + 1 < n + n && s[ptr + 1] == s[n - 1]) ptr++;
                s = s.substr(ptr - n + 1, n);
            }
            s = join(s);
            int ptr = n - 1;
            while (0 < ptr && s[ptr - 1] == s[n]) ptr--;
            s = s.substr(ptr, n);
        }
        return s;
    };
    string res = s;
    FOR(d, 0, n + 1) {
        chkmin(res, func(s, d));
    }
    cout << res << "\n";
}

int main(int argc, char* argv[]) {
    ios_base::sync_with_stdio(0), cin.tie(0);
    if (argc > 1) {
        assert(freopen(argv[1], "r", stdin));
    }
    if (argc > 2) {
        assert(freopen(argv[2], "wb", stdout));
    }
    solve();
    cerr << "\nTime elapsed: " << 1000 * clock() / CLOCKS_PER_SEC << "ms\n";
    return 0;
}


Measured memory_bytes: 384