#include<fstream.h>
int main(void)
{       int mat[100][100];
	long N,M,i,j,suma=0,sumab=0,sumaf=0;
	ifstream in("flip.in");
	in>>N>>M;
	for(i=1;i<=N;i++)
	 for(j=1;j<=M;j++)
	  in>>mat[i][j];
	in.close();
	for(i=1;i<=N;i++)
	for(j=1;j<=M;j++)
	{	suma=suma+mat[i][j];
		if(j==M)
		{if((suma*-1)>suma)suma=suma*-1;
		 sumaf=sumaf+suma;suma=0;
		}
	}
	for(i=1;i<=N;i++)
	for(j=1;j<=M;j++)
	{	sumab=sumab+mat[i][j];
		if(i==N)
		 {if((sumab*-1)>sumab)sumab=sumab*-1;
		  sumaf=sumaf+sumab;sumab=0;
		 }
	}
	ofstream out("flip.out");
	out<<sumaf;
	out.close();
	return 0;
}