#include "fish.h"
#include <bits/stdc++.h>
#define int long long
using namespace std;
map<pair<int,int>, int> a;
vector<vector<int>> fsh;
vector<vector<int>> cfsh;
map<pair<int,pair<int,int>>, int> memo;
int N,M;
int dp(int x, int last, int lastlast){
if(memo.find({x,{last,lastlast}})!=memo.end()) return memo[{x,{last,lastlast}}];
if(x==N) return 0;
memo[{x,{last,lastlast}}] = 0;
for (auto i:fsh[x])
{
int c=dp(x+1, i, last);
if(x>0){
for (auto y:cfsh[x-1]) {
if(y>last&&y<=max(i,lastlast)) c+=a[{x-1,y-1}];
}
}
if(x==N-1) {
for (auto y:cfsh[x]) {
if(y>i&&y<=last) c+=a[{x,y-1}];
}
}
memo[{x,{last,lastlast}}]=max(c, memo[{x,{last,lastlast}}]);
}
return memo[{x,{last,lastlast}}];
}
long long max_weights(signed n, signed m, std::vector<signed> X, std::vector<signed> Y, std::vector<signed> W) {
N=n; M=m;
fsh.resize(N+1, vector<int>(1,0));
cfsh.resize(N+1);
for (int i = 0; i < M; i++){
a[{X[i],Y[i]}] = W[i];
fsh[X[i]+1].push_back(Y[i]+1);
cfsh[X[i]].push_back(Y[i]+1);
if(X[i]>0) {
fsh[X[i]-1].push_back(Y[i]+1);
}
}
for (int i = 0; i < N; i++) sort(fsh[i].begin(),fsh[i].end());
int p=dp(0,0,0);
return p;
}
