#include <iostream>
typedef long long ll;
const int MAX_N = 1000*100 + 10;
const int MAX_S = 2*1000 + 10;
int Vs[MAX_N];
int Ws[MAX_N];
int Ks[MAX_N];
std::pair<int, int> dp[MAX_N][MAX_S];
int solve(int s, int n) {
for (int i = 0; i <= s; ++i) {
ll c = std::min(Ks[0], i / Ws[0]);
dp[0][i] = {c * Vs[0], i - c * Ws[0]};
}
for (int i = 1; i < n; ++i) {
for (int j = 0; j <= s; ++j) {
ll c = std::min(Ks[i], j / Ws[i]);
ll v = c * Vs[i];
ll c2 = std::min(Ks[i], dp[i - 1][j].second / Ws[i]);
ll v2 = c2 * Vs[i];
if (dp[i - 1][j].first + v2 >= dp[i - 1][j - c * Ws[i]].first + v) {
dp[i][j] = {dp[i - 1][j].first + v2, dp[i - 1][j].second - c2 * Ws[i]};
} else {
dp[i][j] = {dp[i - 1][j - c * Ws[i]].first + v, dp[i - 1][j - c * Ws[i]].second};
}
}
}
return dp[n - 1][s].first;
}
int main() {
int s, n; std::cin >> s >> n;
for (int i = 0; i < n; ++i)
std::cin >> Vs[i] >> Ws[i] >> Ks[i];
std::cout << solve(s, n) << std::endl;
}
