#include <bits/stdc++.h>
using namespace std;
const unsigned long long BASE1=131;
const unsigned long long BASE2=13331;
unsigned long long pp[1005];
unsigned long long qp[1005];
unsigned long long h[2005][2005];
int n,m;
string mat[1005];
string bit[2005];
unsigned long long hashing(int r, int c, int hr, int wc)
{
unsigned long long res=h[r+hr][c+wc];
res-=h[r][c+wc]*pp[hr];
res-=h[r+hr][c]*qp[wc];
res+=h[r][c]*pp[hr]*qp[wc];
return res;
}
int compare_rows(int r1, int c1, int r2, int c2, int len)
{
int low=1;
int high=len;
int ans=0;
while(low<=high)
{
int mid=low+(high-low)/2;
if(hashing(r1,c1,1,mid)==hashing(r2,c2,1,mid))
{
ans=mid;
low=mid+1;
}
else
{
high=mid-1;
}
}
if(ans==len)
{
return 0;
}
return (bit[r1][c1+ans]<bit[r2][c2+ans]) ? -1 : 1;
}
int compare_matrices(int r1, int c1, int r2, int c2)
{
int low=1;
int high=n;
int ans=0;
while(low<=high)
{
int mid=(low+high)/2;
if(hashing(r1,c1,mid,m)==hashing(r2,c2,mid,m))
{
ans=mid;
low=mid+1;
}
else
{
high=mid-1;
}
}
if(ans==n)
{
return 0;
}
return compare_rows(r1+ans,c1,r2+ans,c2,m);
}
int main()
{
ios_base::sync_with_stdio(0);
cin.tie(0);
cin>>n>>m;
for(int i=0; i<n; i++)
{
cin>>mat[i];
}
for(int i=0; i<2*n; i++)
{
bit[i].reserve(2*m);
for(int j=0; j<2*m; j++)
{
bit[i]+=mat[i%n][j%m];
}
}
pp[0]=1;
qp[0]=1;
for(int i=1; i<=1000; i++)
{
pp[i]=pp[i-1]*BASE2;
qp[i]=qp[i-1]*BASE1;
}
for(int i=0; i<2*n; i++)
{
unsigned long long row=0;
for(int j=0; j<2*m; j++)
{
row=row*BASE1+(unsigned long long)bit[i][j];
h[i+1][j+1]=h[i][j+1]*BASE2+row;
}
}
int br=-1;
int bc=-1;
for(int c=0; c<m; c++)
{
int i=0;
int j=1;
int k=0;
while(i<n && j<n && k<n)
{
int cmp=compare_rows(i+k,c,j+k,c,m);
if(cmp==0)
{
k++;
}
else
{
if(cmp>0)
{
i+=k+1;
}
else
{
j+=k+1;
}
if(i==j)
{
j++;
}
k=0;
}
}
int rc=min(i,j);
if(br==-1 || compare_matrices(rc,c,br,bc)<0)
{
br=rc;
bc=c;
}
}
for(int i=0; i<n; i++)
{
for(int j=0; j<m; j++)
{
cout<<bit[br+i][bc+j];
}
cout<<endl;
}
return 0;
}
