#include<cstdio>
#include<cmath>
#include<algorithm>
using namespace std;

#define P printf
#define S scanf

int kon , ans , array[1050000],tab[20][20],mx;

void pro( int k , int round , int sum )
{
    if ( round == ans +1 )
    {
        array[sum]++;
        mx = max (array[sum] , mx);
    }
    else
    {
        if ( tab[k][round] == 1 )   pro ( k , round + 1 , sum + pow ( 2 , round-1));
        else if ( tab[k][round] == -1) pro ( k , round + 1 , sum );
        else
        {
            pro ( k , round + 1 , sum + pow ( 2 , round-1));
            pro ( k , round + 1 , sum );
        }
    }
}

int main()
{
    int i,j;
    S("%d%d",&kon,&ans);
    for( i=1 ; i<=kon ; i++ )
    {
        for( j =1 ; j <= ans ; j++ )
        {
            S("%d",&tab[i][j]);
        }
    }
    for( i=1 ; i<=kon ; i++ )   pro ( i , 1 ,0 );
    P("%d",kon - mx);
}