Package for this problem was not updated by the problem writer or Codeforces administration after we’ve upgraded the judging servers. To adjust the time limit constraint, solution execution time will be multiplied by 2. For example, if your solution works for 400 ms on judging servers, then value 800 ms will be displayed and used to determine the verdict.

Virtual contest is a way to take part in past contest, as close as possible to participation on time. It is supported only ACM-ICPC mode for virtual contests.
If you've seen these problems, a virtual contest is not for you - solve these problems in the archive.
If you just want to solve some problem from a contest, a virtual contest is not for you - solve this problem in the archive.
Never use someone else's code, read the tutorials or communicate with other person during a virtual contest.

No tag edit access

B. Steps

time limit per test

2 secondsmemory limit per test

256 megabytesinput

standard inputoutput

standard outputOne day Vasya went out for a walk in the yard but there weren't any of his friends outside and he had no one to play touch and run. But the boy didn't lose the high spirits and decided to play touch and run with himself. You may ask: "How did he do that?" The answer is simple.

Vasya noticed that the yard is a rectangular *n* × *m* field. The squares have coordinates (*x*, *y*) (1 ≤ *x* ≤ *n*, 1 ≤ *y* ≤ *m*), where *x* is the index of the row and *y* is the index of the column.

Initially Vasya stands in the square with coordinates (*x*_{c}, *y*_{c}). To play, he has got a list of *k* vectors (*dx*_{i}, *dy*_{i}) of non-zero length. The game goes like this. The boy considers all vectors in the order from 1 to *k*, and consecutively chooses each vector as the current one. After the boy has chosen a current vector, he makes the maximally possible number of valid steps in the vector's direction (it is possible that he makes zero steps).

A step is defined as one movement from the square where the boy is standing now, in the direction of the current vector. That is, if Vasya is positioned in square (*x*, *y*), and the current vector is (*dx*, *dy*), one step moves Vasya to square (*x* + *dx*, *y* + *dy*). A step is considered valid, if the boy does not go out of the yard if he performs the step.

Vasya stepped on and on, on and on until he ran out of vectors in his list. Ha had been stepping for so long that he completely forgot how many steps he had made. Help the boy and count how many steps he had made.

Input

The first input line contains two integers *n* and *m* (1 ≤ *n*, *m* ≤ 10^{9}) — the yard's sizes. The second line contains integers *x*_{c} and *y*_{c} — the initial square's coordinates (1 ≤ *x*_{c} ≤ *n*, 1 ≤ *y*_{c} ≤ *m*).

The third line contains an integer *k* (1 ≤ *k* ≤ 10^{4}) — the number of vectors. Then follow *k* lines, each of them contains two integers *dx*_{i} and *dy*_{i} (|*dx*_{i}|, |*dy*_{i}| ≤ 10^{9}, |*dx*| + |*dy*| ≥ 1).

Output

Print the single number — the number of steps Vasya had made.

Please do not use the %lld specificator to read or write 64-bit integers in С++. It is preferred to use the cin, cout streams or the %I64d specificator.

Examples

Input

4 5

1 1

3

1 1

1 1

0 -2

Output

4

Input

10 10

1 2

1

-1 0

Output

0

Note

In the first sample Vasya is initially positioned at square (1, 1) and makes 3 steps by the first vector (1, 1). So, he consecutively visits the squares (2, 2), (3, 3), (4, 4). Then he makes 0 steps by the second vector (1, 1). He makes 1 more step by the third vector (0, - 2) and he ends up in square (4, 2). Overall, Vasya makes 4 steps.

In the second sample Vasya is initially positioned in square (1, 2) and makes 0 steps by vector ( - 1, 0), as the square with coordinates (0, 2) is located outside the yard.

Codeforces (c) Copyright 2010-2017 Mike Mirzayanov

The only programming contests Web 2.0 platform

Server time: Jun/28/2017 05:06:23 (c2).

Desktop version, switch to mobile version.

User lists

Name |
---|