#include <iostream>
#include <fstream>
using namespace std;
int main ()
{
	long long  tb[18][18], sumpoz, sumneg;
	int m, n, i, j;
	ifstream fi("flip.in");
	ofstream fo("flip.out");
	fi>>n>>m;
	for(i=1;i<=n;i++)
	{
		sumpoz=sumneg=0;
		for(j=1;j<=m;j++)
		{
			fi>>tb[i][j];
			if(tb[i][j]>0) sumpoz+=tb[i][j];
			if(tb[i][j]<0) sumneg+=tb[i][j];
			if(j==m)
			{
				tb[0][j]=sumpoz;
				tb[i+1][j]=sumneg;
			}
		}
	}
	for(j=1;j<=m;j++)
	{
		sumpoz=sumneg=0;
		for(i=1;i<=n;i++)
		{
			if(tb[i][j]>0) sumpoz+=tb[i][j];
			if(tb[i][j]<0) sumneg+=tb[i][j];
			if(i==n)
			{
				tb[i][0]=sumpoz;
				tb[i][j+1]=sumneg;
			}
		}
	}
	fi.close();
	fo.close();
	return 0;
}