#include<bits/stdc++.h>
using namespace std;
int a[10005][4],s[10005][4];
int n,m;
int main()
{
	cin>>n>>m;
	for(int i=1;i<=n;i++)
	{
		for(int j=1;j<=3;j++)
		{
			cin>>a[i][j];
			s[i][j]=s[i][j-1]+s[i-1][j]-s[i-1][j-1]+a[i][j];
		}
	}
	int x2,y2,sum,max=-2e9;
	for(int x=1;x<=n-m+1;x++)
	{
		for(int y=1;y<=4-m;y++)
		{
			x2=x+m-1;
			y2=y+m-1;
			sum=s[x2][y2]-s[x-1][y2]-s[x2][y-1]+s[x-1][y-1];
			if(sum>max)
			{
				max=sum;
			}
		}
	}
	cout<<sum;
	return 0;
}