#include<bits/stdc++.h>
using namespace std;
typedef  long long ll;
template<class T> inline bool chmin(T& a, T b) {if (a > b) {a = b;return true;}return false;}
template<class T> inline bool chmax(T& a, T b) {if (a < b) {a = b;return true;}return false;}
//自作関数
template<class T> ll llpow(T x,T n){ll ans=1;while(n--){ans*=x;}return ans;}

#define rep(i,b,n) for(ll i=b;i<(ll)n;i++)
#define rep2(i, begin_i, end_i) for (ll i = (ll)begin_i; i < (ll)end_i; i++)

long long INF = 1LL<<60;
int n;
int main(){
    int n;
    int k; string s;
    cin>>n>>k>>s;
    string buff;
    rep(i,0,n-k+1){
        buff+=s[i+k-1];
    }
    string add=s.substr(0,k-1);
    if((n-k-1)%2){
        reverse(add.begin(),add.end());
    }
    buff+=add;
    cout<<buff<<endl;
    return 0;
}