#include <bits/stdc++.h>
#define SQR(x) (1LL * ((x) * (x)))
#define MASK(i) (1LL << (i))
#define BIT(x, i) (((x) >> (i)) & 1)
#define fi first
#define se second
#define pb push_back
#define all(x) x.begin(), x.end()
#define rall(x) x.rbegin(), x.rend()
#define sz(s) (int)s.size()
#define prev __prev
#define next __next
#define left __left
#define right __right
#define mp make_pair
#define pii pair<int, int>
#define pll pair<ll, ll>
#define vi vector<int>
#define vll vector<ll>
typedef long long ll;
typedef unsigned long long ull;
typedef long double ld;
typedef unsigned int ui;
using namespace std;
const int mod = 1e9 + 7;
const int INF = 1e9 + 7;
const ll INFLL = (ll)2e18 + 7LL;
const ld PI = acos(-1);
const int dx[] = {1, -1, 0, 0, -1, 1, 1, -1};
const int dy[] = {0, 0, 1, -1, -1, -1, 1, 1};
template<class BUI, class TRONG>
bool minimize(BUI &x, const TRONG y){
if(x > y){
x = y;
return true;
} else return false;
}
template<class BUI, class TRONG>
bool maximize(BUI &x, const TRONG y){
if(x < y){
x = y;
return true;
} else return false;
}
/* Author : Bui Nguyen Duc Trong, Luong Van Chanh High School for the gifted*/
/* Template is copied by Trong */
/** Losing in Provincial Contests **/
/** TRYING HARDER**/
/** ORZ **/
/* -----------------[ MAIN CODE GOES HERE ]----------------- */
mt19937 rng(chrono::steady_clock::now().time_since_epoch().count());
const int N = 2020;
int n, S;
ll f[2][N];
ll cost(int prev, int x, int y, int W, int V){
assert((x - y) % W == 0);
return f[prev][y] + 1LL * ((x - y) / W) * V;
}
void solve(){
cin >> S >> n;
for(int i = 1; i <= n; i++){
int ni = i & 1;
int nj = (i - 1) & 1;
for(int j = 0; j <= S; j++) f[ni][j] = 0;
ll V, W, K; cin >> V >> W >> K;
vector<deque<int>> dq(W);
for(int j = 0; j <= S; j++){
int z = j % W;
if(!dq[z].empty() && j - dq[z].front() > 1LL * K * W) dq[z].pop_front();
while(!dq[z].empty() && cost(nj, j, j, W, V) >= cost(nj, j, dq[z].front(), W, V)) dq[z].pop_back();
dq[z].push_back(j);
f[ni][j] = cost(nj, j, dq[z].front(), W, V);
}
}
ll ans = 0;
for(int i = 1; i <= S; i++) maximize(ans, f[n & 1][i]);
cout << ans << '\n';
}
/*
15 5
4 12 1
2 1 1
10 4 1
1 1 1
2 2 1
*/
signed main()
{
ios_base::sync_with_stdio(false);
cin.tie(0); cout.tie(0);
const bool multitest = 0;
int tt = 1; if(multitest) cin >> tt;
while( tt-- ){
solve();
}
return 0;
}
