#include <iostream>
#include <vector>
#include <algorithm>
#include <queue>
#include <set>
#include <map>
#define INF 1e9
using namespace std;
typedef long long ll;
void solve()
{
int l, n; cin >> l >> n;
vector<int>dp(n + 1, 1), t(n + 1), v(n + 1);
for (int i = 1; i <= n; i++) cin >> t[i] >> v[i];
for (int i = n - 1; i >= 1; i--) {
for (int j = i + 1; j <= n; j++) {
if (((l / v[i]) + t[i]) > ((l / v[j]) + t[j]))dp[i] = max(dp[i], dp[j] + 1);
}
}
int ans = 0;
for (int i = 1; i <= n; i++) ans = max(ans, dp[i]);
cout << ans << "\n";
}
int main()
{
ios_base::sync_with_stdio(0);
cin.tie(0);
int t = 1;// cin>>t;
while (t--) solve();
return 0;
}
