#include<cstdio>
#include<iostream>
using namespace std;

FILE *f = fopen("dreptpal.in", "r");
FILE *g = fopen("dreptpal.out", "w");

#define MaxN 1010

int N, M;
int A[MaxN][MaxN], B[MaxN][MaxN];

void citire(void)
{
    fscanf (f, "%d %d", &N, &M);
    for (int i=1;i<=N;i++)
        for (int j=1;j<=M;j++)
            fscanf (f, "%d ", &A[i][j]);
}

void aflarePalindromLinie(void)
{
    for (int i=1;i<=N;i++)
    {
        A[i][0] = -1;

        int dr = 0, pivot = 0;
        for (int j=1;j<=M;j++)
        {
            int known = dr > j ? min (B[i][(pivot << 1) - j]>>1, dr - j) : 1;

            for (;A[i][j - known] == A[i][j + known]; ++ known);

            if (dr <= j + known)
                dr = j + known,
                pivot = j;

            B[i][j] = (known << 1) - 1;
        }
    }
}

int main()
{
    citire();
    aflarePalindromLinie();
    
/*    for (int i=1;i<=N;i++)
    {
        for (int j=1;j<=M;j++)
            cout << B[i][j] << " ";
        cout << "\n";
    }*/
}