#include <bits/stdc++.h>

using namespace std;
#define ll long long
#define maxn 1000010
#define pb push_back
ifstream in("flip.in");
ofstream out("flip.out");
    ll n,a[20][20],m,s[20][20], cur_ans, ans, sum[maxn], total ;
int main()
{
in>>n>>m;
for(int i=0;i<n;i++)
    for(int j=0;j<m;j++)
{
    in>>a[i][j];
    sum[j]+=a[i][j];

}
for(int mask=0;mask<(1<<n);mask++)
{
    for(int i=0;i<n;i++)
    for(int j=0;j<m;j++)
        s[i][j]=a[i][j];
    for (int i = 0;i < n;++i)
    if ((mask&(1<<i)) == (1 << i))
    for (int j = 0;j < m;++j)
    s[i][j] *= -1;
    ll cur = 0;
    for (int j = 0;j < m;++j)
    {
    ll sum = 0;
    for (int i = 0;i < n;++i)
    sum += s[i][j];
    sum = abs(sum);
    cur += sum;
    }
    ans = max(ans,cur);
}
out<<ans;
}