#include <bits/stdc++.h>
#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/tree_policy.hpp>
using namespace __gnu_pbds;
using namespace std;
template <class T>
using indexed_set = tree<int, null_type, less<int>, rb_tree_tag, tree_order_statistics_node_update>;
const long long M = 1000000007;
#define multiply(a, b) ((a % M) * (b % M)) % M
#define all(a) (a).begin(), (a).end()
#define ll long long
#define ld long double
#define max(a, b) (a > b ? a : b)
#define loop(i, a, b) for (long long i = a; i < b; i++)
#define rloop(i, a, b) for (int i = a; i >= b; i--)
#define logarr(arr, a, b) for (int i = a; i < b; i++) cout << arr[i] << " "; cout << endl
#define vi vector<int>
#define pi pair<int, int>
#define f first
#define s second
#define pb push_back
#define pob pop_back
#define p push
#define po pop
#define gcd(a, b) __gcd(a, b)
#define yes "YES\n"
#define no "NO\n"
// find_by_order -> iterator to value
// order_of_key -> index where value is/will be
long long binary_expo(long long x, long long n) {
if (n == 0) return 1;
if (n == 1) return x % M;
long long temp = binary_expo(x, n / 2);
temp = multiply(temp, temp);
if (n % 2) temp = multiply(temp, x);
return temp;
}
signed main() {
ios::sync_with_stdio(false); cin.tie(NULL);
ll n, s;
cin >> s >> n;
vector<priority_queue<pair<ll, ll>>> trk(s + 1);
ll x, y, z;
loop(i, 0, n) {
cin >> x >> y >> z;
trk[y].push(make_pair(x, z));
}
vector<ll> prev(s + 1, LLONG_MIN), nxt(s + 1, LLONG_MIN);
prev[0] = 0; // Initialization for the base case
ll p = -1;
vector<pair<ll, ll>> vec;
for (ll ind = 1; ind <= s; ind++) {
if (trk[ind].empty()) continue;
nxt = prev; // Start with the current state of prev
vec.clear(); // Clear vec for each track
while (!trk[ind].empty()) {
vec.push_back(trk[ind].top());
trk[ind].pop();
}
ll sz = vec.size();
for (ll sum = 0; sum <= s; sum++) {
ll notake = prev[sum];
ll take = LLONG_MIN;
ll sm = 0, prof = 0, i = 0;
while (i < sz && sum - sm >= 0) {
ll val = vec[i].first;
ll time = vec[i].second;
prof += val;
sm += ind;
while (time-- && sum - sm >= 0) {
if (prev[sum - sm] != LLONG_MIN) {
take = max(take, prof + prev[sum - sm]);
}
prof += val;
sm += ind;
}
prof -= val;
sm -= ind;
i++;
}
nxt[sum] = max(notake, take);
}
prev = nxt; // Move to the next state
}
ll maxprof = 0;
for (ll i = 0; i <= s; i++) {
if (prev[i] != LLONG_MIN) maxprof = max(maxprof, prev[i]);
}
std::cout << maxprof << endl;
return 0;
}
