Karafs is some kind of vegetable in shape of an 1 × h rectangle. Tavaspolis people love Karafs and they use Karafs in almost any kind of food. Tavas, himself, is crazy about Karafs.

Each Karafs has a positive integer height. Tavas has an infinite 1-based sequence of Karafses. The height of the i-th Karafs is si = A + (i - 1) × B.

For a given m, let’s define an m-bite operation as decreasing the height of at most m distinct not eaten Karafses by 1. Karafs is considered as eaten when its height becomes zero.

Now SaDDas asks you n queries. In each query he gives you numbers l, t and m and you should find the largest number r such that l ≤ r and sequence sl, sl + 1, …, sr can be eaten by performing m-bite no more than t times or print -1 if there is no such number r. Input

The first line of input contains three integers A, B and n (1 ≤ A, B ≤ 106, 1 ≤ n ≤ 105).

Next n lines contain information about queries. i-th line contains integers l, t, m (1 ≤ l, t, m ≤ 106) for i-th query. Output

For each query, print its answer in a single line. Examples Input Copy

2 1 4 1 5 3 3 3 10 7 10 2 6 4 8

Output Copy

4 -1 8 -1

Input Copy

1 5 2 1 5 10 2 7 4

Output Copy

1 2

思路： 必須得滿足 Max { a [ i ] }<= t && sum{ a [ i ] } <=m*T ; 那麼我們先求出上界 R， 反解 A+(R-1)*B<=T 即可； 然後二分mid ；

** 二分一定得會寫！！** lyd 老師的書上提供了求其前驅和後繼的兩種寫法，注意配套使用；

#include<iostream>
#include<cstdio>
#include<algorithm>
#include<cstdlib>
#include<cstring>
#include<string>
#include<cmath>
#include<map>
#include<set>
#include<vector>
#include<queue>
#include<bitset>
#include<ctime>
#include<deque>
#include<stack>
#include<functional>
#include<sstream>
#include<cctype>
//#pragma GCC optimize("O3")
using namespace std;
#define maxn 100005
#define inf 0x3f3f3f3f
#define INF 0x7fffffff
#define rdint(x) scanf("%d",&x)
#define rdllt(x) scanf("%lld",&x)
typedef long long  ll;
typedef unsigned long long ull;
typedef unsigned int U;
#define ms(x) memset((x),0,sizeof(x))
const int mod = 10000007;
#define Mod 20100403
#define sq(x) (x)*(x)
#define eps 1e-7
typedef pair<int, int> pii;


inline int rd() {
	int x = 0;
	char c = getchar();
	bool f = false;
	while (!isdigit(c)) {
		if (c == '-') f = true;
		c = getchar();
	}
	while (isdigit(c)) {
		x = (x << 1) + (x << 3) + (c ^ 48);
		c = getchar();
	}
	return f ? -x : x;
}

ll gcd(ll a, ll b) {
	return b == 0 ? a : gcd(b, a%b);
}
ll sqr(ll x) { return x * x; }


ll A, B, n;
ll l, m, t;
ll digt(ll i) {
	return A + (i - 1)*B;
}

ll calSum(ll r) {
	return (digt(l) + digt(r))*(r - l + 1) / 2;
}

int main()
{
	//ios::sync_with_stdio(false);
	rdllt(A); rdllt(B); rdllt(n);
	while (n--) {
		rdllt(l); rdllt(t); rdllt(m);
		ll r = (t - A) / B + 1;
		if (r < l) {
			cout << -1 << endl; continue;
		}
		ll L = l, R = r;
		while (L < R) {
			ll mid = (L + R + 1) >> 1;
			if (calSum(mid) <= t * m)L = mid;
			else R = mid - 1;
		}
		cout << L << endl;
	}
}