#include <bits/stdc++.h>
#define pb push_back
#define fst first
#define snd second
#define fore(i,a,b) for(int i=a,pao=b;i<pao;++i)
#define SZ(x) ((int)x.size())
#define ALL(x) x.begin(),x.end()
#define mset(a,v) memset((a),(v),sizeof(a))
#define FIN ios::sync_with_stdio(0);cin.tie(0);cout.tie(0)
using namespace std;
typedef long long ll;
const int MAXN=300,MAXY=10;
ll pref[MAXN][MAXY];
long long max_weights(int N, int M, std::vector<int> X, std::vector<int> Y, std::vector<int> W) {
int lim=*max_element(ALL(Y))+1;
fore(i,0,M){
pref[X[i]][Y[i]+1]+=W[i];
}
fore(i,0,N){
fore(j,1,lim+1){
pref[i][j]+=pref[i][j-1];
}
}
vector<vector<ll>>dp(10,vector<ll>(10,0));
fore(l,0,10)fore(r,0,10){
dp[l][r]=pref[0][r]-pref[0][l];
}
fore(i,1,N-1){
vector<vector<ll>>ndp(10,vector<ll>(10,0));
fore(l,0,10){
fore(m,0,10){
fore(r,0,10){
ndp[m][r]=max(ndp[m][r],dp[l][m]+(pref[i][max(l,r)]-pref[i][m]));
}
}
}
dp.swap(ndp);
}
ll ans=0;
fore(l,0,10)fore(r,0,10){
ans=max(ans,dp[l][r]+(pref[N-1][l]-pref[N-1][r]));
}
return ans;
}
