#include <bits/stdc++.h>
using namespace std;
using lint = long long;
using pli = pair<lint, int>;
const int MAX_N = 1e5 + 5, MAX_S = 2000 + 5;
int s, n;
lint v[MAX_N];
int w[MAX_N], k[MAX_N];
lint dp[2][MAX_S];
unordered_map<int, deque<pli>> trans[MAX_N];
int main() {
// freopen("knapsack.in", "r", stdin);
cin >> s >> n;
for (int i = 1; i <= n; i++) {
cin >> v[i] >> w[i] >> k[i];
k[i] = min(k[i], s);
}
for (int i = n; i >= 1; i--) {
int parity = i % 2, opp_parity = (i + 1) % 2;
for (int c = 0; c <= s; c++) {
if (c < w[i]) {
trans[i][c].push_back({dp[opp_parity][c], c});
dp[parity][c] = dp[opp_parity][c];
} else {
lint val = dp[opp_parity][c] - v[i] * (c / w[i]);
while (trans[i][c % w[i]].size() && trans[i][c % w[i]].back().first <= val)
trans[i][c % w[i]].pop_back();
trans[i][c % w[i]].push_back({val, c});
while (trans[i][c % w[i]].front().second < c - k[i] * w[i])
trans[i][c % w[i]].pop_front();
int new_c = trans[i][c % w[i]].front().second;
dp[parity][c] = dp[opp_parity][new_c] + v[i] * ((c - new_c) / w[i]);
}
// cout << i << " " << c << ": " << dp[parity][c] << endl;
}
}
cout << dp[1][s] << '\n';
}
