#include <bits/stdc++.h>
#define ll long long
#define pii pair<ll, ll>
#define pllk pair<long long, long long>
#define M 1000000007
#define INF 0x5ADFACE5
#define LINF 0x51DEEFFEC7C0DECALL
#define N (1<<17)
using namespace std;
pii v[14][N];
vector<pii> w[14];
int c[14];
int x[111111];
ll ans = 0;
ll s = 0;
int n, m;
void lol () {
for (int i = 0; i < 10000; i++) {
int a = rand() % n;
int b = rand() % n;
if (a == b) continue;
int oa = c[a];
int ob = c[b];
s -= w[a][c[a]].first;
s -= w[b][c[b]].first;
x[w[a][c[a]].second]--;
x[w[b][c[b]].second]--;
s += w[a][ob].first;
x[w[a][ob].second]++;
int k = 0;
while (x[w[b][k].second]) k++;
s += w[b][k].first;
x[w[b][k].second]++;
if (s <= ans) {
s -= w[a][ob].first;
s -= w[b][k].first;
s += w[a][oa].first;
s += w[b][ob].first;
x[w[a][c[a]].second]++;
x[w[b][c[b]].second]++;
x[w[a][ob].second]--;
x[w[b][k].second]--;
} else {
c[a] = ob;
c[b] = k;
ans = s;
}
}
}
int main () {
srand(time(0));
cin>>n>>m;
for (int i = 0; i < n; i++) {
for (int j = 0; j < m; j++) cin>>v[i][j].first, v[i][j].second = j;
sort(v[i], v[i] + m);
reverse(v[i], v[i] + m);
for (int j = 0; j < n; j++) w[i].push_back(v[i][j]);
}
if (n == 1) {
cout<<v[0][0].first<<endl;
} else if (false) {
if (v[0][0].second == v[1][0].second) {
cout<<max(v[0][0].first + v[1][1].first, v[0][1].first + v[1][0].first)<<endl;
} else cout<<v[0][0].first + v[1][0].first<<endl;
} else {
int q[n];
for (int i = 0; i < n; i++) {
q[i] = i;
}
ll ma = 0;
for (int i = 0; i < 25; i++) {
random_shuffle(q, q + n);
for (int i : q) x[w[i][c[i].second]--;
for (int i : q) {
c[i] = 0;
while (x[w[i][c[i]].second]) c[i]++;
x[w[i][c[i]].second]++;
s += w[i][c[i]].first;
}
ans = s;
lol();
ma = max(ans, ma);
}
cout<<ma<<endl;
}
}