#include "fish.h"
#include <bits/stdc++.h>
using namespace std;
#define INF (long long)(1e18)
const int N = 3005;
long long a[N][N];
long long dp[N][N][2];
long long max_weights(int n, int m, vector<int> x, vector<int> y, vector<int> w) {
if (n > 3000) return 0LL;
for (int i = 0; i < m; i++){
a[x[i] + 1][y[i] + 1] += w[i];
}
for (int i = 1; i <= n; i++){
for (int j = 1; j <= n; j++){
a[i][j] += a[i][j - 1];
}
}
for (int i = 0; i < N; i++){
for (int j = 0; j < N; j++){
dp[i][j][0] = dp[i][j][1] = -INF;
}
}
dp[0][0][1] = 0; //0, 1 --> not processed / processed row
for (int i = 1; i <= n + 1; i++){
//0--> inc, 1--> dec when not 0
//start bitonic sequence
if (i != (n + 1)){
for (int j = 1; j <= n; j++){
dp[i][j][0] = max(dp[i][j][0], dp[i - 1][0][0] + a[i - 1][j] - a[i][j]);
dp[i][j][0] = max(dp[i][j][0], dp[i - 1][0][1] - a[i][j]);
}
//continue bitonic --> increasing
long long mx = -INF;
for (int j = 1; j <= n; j++){
mx = max(mx, dp[i - 1][j][0]);
dp[i][j][0] = max(dp[i][j][0], mx - a[i][j] + a[i - 1][j]);
}
mx = -INF;
for (int j = n; j >= 1; j--){
mx = max(mx, dp[i - 1][j][1]);
dp[i][j][1] = max(dp[i][j][1], mx - a[i][j] + a[i + 1][j]);
}
//switch from inc to dec
for (int j = 1; j <= n; j++){
dp[i][j][1] = max(dp[i][j][1], dp[i][j][0] + a[i][j] + a[i + 1][j]);
}
}
//end bitonic
for (int j = 1; j <= n; j++){
dp[i][0][0] = max(dp[i][0][0], dp[i - 1][j][1] - a[i][j]);
dp[i][0][1] = max(dp[i][0][1], dp[i - 1][j][1]);
}
dp[i][0][0] = max(dp[i][0][0], dp[i - 1][0][0]);
dp[i][0][0] = max(dp[i][0][0], dp[i - 1][0][1]);
}
long long ans = -INF;
ans = max(ans, dp[n + 1][0][0]);
ans = max(ans, dp[n + 1][0][1]);
return ans;
}
// int main(){
// int n, m; cin >> n >> m;
// vector <int> a(m), b(m), c(m);
// for (auto &x : a) cin >> x;
// for (auto &x : b) cin >> x;
// for (auto &x : c) cin >> x;
// cout << max_weights(n, m, a, b, c) << "\n";
// return 0;
// }
