# 最小費用流(minimum cost flow)
class MinCostFlow:
    def __init__(self, n):
        self.n = n
        self.G = [[] for i in range(n)]

    def add_edge(self, f, t, cap, cost):
        # [to, cap, cost, rev]
        self.G[f].append([t, cap, cost, len(self.G[t])])
        self.G[t].append([f, 0, -cost, len(self.G[f])-1])

    def flow(self, s, t, f):
        n = self.n
        G = self.G
        prevv = [0]*n; preve = [0]*n
        INF = 10**18+7

        res = 0
        while f:
            dist = [INF]*n
            dist[s] = 0
            update = 1
            while update:
                update = 0
                for v in range(n):
                    if dist[v] == INF:
                        continue
                    gv = G[v]
                    for i in range(len(gv)):
                        to, cap, cost, rev = gv[i]
                        if cap > 0 and dist[v] + cost < dist[to]:
                            dist[to] = dist[v] + cost
                            prevv[to] = v; preve[to] = i
                            update = 1
            if dist[t] == INF:
                return -1

            d = f; v = t
            while v != s:
                d = min(d, G[prevv[v]][preve[v]][1])
                v = prevv[v]
            f -= d
            res += d * dist[t]
            v = t
            while v != s:
                e = G[prevv[v]][preve[v]]
                e[1] -= d
                G[v][e[3]][1] += d
                v = prevv[v]
        return res

n, m = map(int, input().split())
A = []
for i in range(n):
    l = list(map(int, input().split()))
    if n % 2 and i == n // 2:
        continue
    A.append(l[:])

n -= n % 2

mf = MinCostFlow(n+2)
M = 1 << 40
s = n
t = s + 1
k = n // 2
for now in range(k):
    mf.add_edge(s, now, 1, 0)
    mf.add_edge(now+k, t, 1, 0)
    for nxt in range(k, 2*k):
        d = 0
        for i in range(m):
            d = max(d, A[nxt][i] - A[now][i])
        #print(now, nxt, d)
        mf.add_edge(now, nxt, 1, M-d)

ans = mf.flow(s, t, k)
print(M*k-ans)