#include "bits/stdc++.h"

using namespace std;

int main(){
    int n, k;cin>>n>>k;
    int tmp=0;
    for(int i=0;i<n;i++){
        string S;cin>>S;
        if(tmp+S.size()>k){
            cout<<endl;
            tmp=S.size();
        } else {
            if(tmp)cout<<" ";
            tmp+=S.size();
        }
        cout<<S;
    }
}