#include <bits/stdc++.h>
#define pb push_back
#define S second
#define F first
#define FOR(x, n, m, d) for(int x = n; x <= m; x += d)
#define FORR(x, n, m, d) for(int x = n; x >= m; x -= d)
#define nikita ios_base::sync_with_stdio(0), cin.tie(0);
#define int long long
using namespace std;
const int N = 2050;
int n, cost, weight, number, m, ans;
int dp[N], dp1[N][N], x, y;
vector<pair<int, int>>g[N];
vector<int>v[N];
signed main(){
cin >> m >> n;
FOR(i, 1, n,1 ){
cin >> cost >> weight >> number;
if(weight <= m)g[weight].pb({cost, number});
}
FOR(i, 1, m, 1)sort(g[i].begin(), g[i].end());
FOR(i, 1, m, 1){
for(auto j : g[i]){
while(j.S != 0 && v[i].size() < m/i)v[i].pb(j.F), j.S --;
}
}
ans = 0;
FOR(i, 1, m, 1){
dp[i] = -1e18;
y=-1;
FORR(j, i-1, 0, 1){
x = i-j;
if(dp[i] < dp[j])dp[i] = dp[j], y = j;
if(v[x].size() >= 1 + dp1[j][x] && dp[i] < dp[j] + v[x][ v[x].size() - 1 - dp1[j][x] ]){
dp[i] = dp[j] + v[x][ v[x].size() - 1 - dp1[j][x] ];
y = j;
}
}
if(y==-1)continue;
FOR(j, 1, m, 1)dp1[i][j] += dp1[y][j];
dp1[i][i-y] ++;
ans = max(ans, dp[i]);
}
cout << ans;
}
