#include<bits/stdc++.h>
using namespace std;
#define sync ios_base::sync_with_stdio(false), cin.tie(NULL)
#define F first
#define S second
#define pb emplace_back
#define mt make_tuple
#define mp make_pair
#define gcd __gcd
#define PI 3.141592653589
// Input
#define in(a) scanf("%d",&a)
#define in2(a,b) scanf("%d%d",&a,&b)
#define in3(a,b,c) scanf("%d%d%d",&a,&b,&c)
#define llin(a) cin >> a
#define inl(a) scanf("%lld",&a)
#define read(v,i,n) for(i=0;i<n;i++)in(v[i])
#define twod(mat,i,j,n,m) rep(i,n){rep(j,m)in(mat[i][j]);}
#define sc(ch) scanf("%c",&ch)
#define sstr(str) scanf("%s",str)
// Output
#define pr(a) printf("%d ",a)
#define pr2(a,b) printf("%d %d\n",a,b)
#define pr3(a,b,c) printf("%d %d %d\n",a,b,c)
#define out(a) printf("%d\n",a)
#define outl(a) printf("%lld\n",a)
#define llpr(a) cout << a << " "
#define llout(a) cout << a << "\n"
#define yes printf("YES\n")
#define no printf("NO\n")
#define lin printf("\n")
// Iterator
#define lp(i,a,b) for(i=a;i<b;i++)
#define rep(i,n) for(i=0;i<n;i++)
#define all(vec) vec.begin(),vec.end()
#define lower(v,k) lower_bound(v.begin(),v.end(),k)-v.begin()
#define upper(v,k) upper_bound(v.begin(),v.end(),k)-v.begin()
#define tf(mytuple) get<0>(mytuple)
#define ts(mytuple) get<1>(mytuple)
#define tt(mytuple) get<2>(mytuple)
// Debug
#define dbg(v,i,n) for(i=0;i<n;i++)pr(v[i]); lin
#define what(x) cerr << #x << " : " << x << "\n"
#define ck printf("continue\n")
#define debug(args...) { string _s = #args; replace(_s.begin(), _s.end(), ',', ' '); stringstream _ss(_s); istream_iterator<string> _it(_ss); err(_it, args); }
void err(istream_iterator<string> it) {}
template<typename T, typename... Args>
void err(istream_iterator<string> it, T a, Args... args)
{
	cerr << *it << " = " << a << "\n";
	err(++it, args...);
}
// Data Type
#define ll long long int
#define ii pair<int,int>
#define pli pair<ll,int>
#define triple tuple<int,int,int>
#define vi vector<int>
#define vii vector<pair<int,int> >
#define vvi vector<vector<int> >
#define viii vector<pair<pair<int,int>,int> >
#define vvii vector<vector<pair<int,int> > >
#define M 1000000007
#define N 5005  //check the limits, man
const ll INF = 1e18;
ll dp[N][N];
int ar[N][205];
int v[N],lft[N],rgt[N];
ll dis[N];
int main()
{
    int n,m,i,j,l,r,a;
    in2(n,m);
    lp(i,1,n)
        in(dis[i]);
    lp(i,1,n+1)
    {
        lp(j,1,m+1)
            in(ar[i][j]);
    }
    stack<int> st;
    lp(j,1,m+1)
    {
        lp(i,1,n+1)
            v[i]=ar[i][j];
        v[n+1]=M,i=1;
        while(i<=n || !st.empty())
        {
            if(st.empty())
            {
                lft[i]=1;
                st.push(i);
                i++;
            }
            else
            {
                a=st.top();
                if(v[i]<=v[a])
                {
                    lft[i]=a+1;
                    st.push(i);
                    i++;
                }
                else
                {
                    rgt[a]=i-1;
                    st.pop();
                }
            }
        }
        lp(i,1,n+1)
        {
            l=lft[i],r=rgt[i];
            dp[l][i]+=v[i];
            dp[l][r+1]-=v[i];
            dp[i+1][i]-=v[i];
            dp[i+1][r+1]+=v[i];
        }
    }
    lp(i,1,n+1)
    {
        lp(j,1,n+1)
            dp[i][j]+=(dp[i-1][j]+dp[i][j-1]-dp[i-1][j-1]);
    }
    lp(i,1,n)
        dis[i]+=dis[i-1];
    ll ans=0;
    lp(i,1,n+1)
    {
        lp(j,i,n+1)
            dp[i][j]-=(dis[j-1]-dis[i-1]),ans=max(ans,dp[i][j]);
    }
    llout(ans);
}



Measured memory_bytes: 199936