#include <bits/stdc++.h>
#define lop(i,a,b) for(ll i = a; i < b; i++)
#define alop(i,v) for(auto &i: v)
#define in(v) for(auto &i: v) cin >> i;
#define ll long long
#define endl "\n"
#define pb push_back
#define all(v) v.begin(),v.end()
#define mem(dp, x) memset(dp, x, sizeof(dp))
#define F first
#define S second
using namespace std;
ll mod = 2019;
const ll N = 1e5;
bool cmp(pair<ll, ll> a, pair<ll, ll> b) {
if(a.first == b.first) return a.second < b.second;
return a.first > b.first;
}
signed main()
{
int n, s; cin >> s >> n;
vector<array<ll, 3>> v(n); // {value, weight, copies}
vector<pair<ll, ll>> arr(1);
alop(i, v){
in(i);
ll temp = (s / i[1]) + 1, p = 1;
while(i[2] > 0 && temp > 0){
arr.pb({i[0] * p, i[1] * p});
i[2] -= p, temp -= p;
if(i[2] - (p + 1) >= 0 && temp - (p + 1) >= 0) p++;
else p = min(i[2], temp);
}
}
sort(arr.begin() + 1, arr.end(), cmp);
n = arr.size() - 1;
ll dp[n + 1][s + 1] = {};
for(int i = 1; i <= n; i++){
for(int j = 1; j <= s; j++){
dp[i][j] = dp[i - 1][j];
if(j - arr[i].second >= 0) dp[i][j] = max(dp[i][j], dp[i - 1][j - arr[i].second] + arr[i].first);
}
}
cout << dp[n][s];
return 0;
}
