#include <bits/stdc++.h>
#define pb push_back
#define eb emplace_back
#define sz(x) (int)x.size()
#define all(x) x.begin(), x.end()
#define uniq(x) x.erase(unique(all(x)), x.end())
#define rall(x) x.rbegin(), x.rend()
using namespace std;
using ll = long long;
using ull = unsigned long long;
using ld = long double;
using pii = pair<int, int>;
using pll = pair<ll, ll>;
const int mod = 1e9 + 7;
const int LOG = 20;
const int maxn = 1e5 + 5;
void setIO() {
ios_base::sync_with_stdio(false);
cin.tie(0);
cout.tie(0);
}
struct Item { int v, w, k; };
int32_t main() {
setIO();
int s, n;
cin >> s >> n;
int mx = 0;
vector<Item> v(n);
for(Item &it : v) cin >> it.v >> it.w >> it.k, mx = max(mx, it.k);
if(n == 1) {
cout << min(s / v[0].w, v[0].k) * v[0].v << '\n';
}
if(mx == 1) {
}
return 0;
}
