Winter in Yekaterinburg is the longest time of the year. And everyone
spends long winter evenings in his own way. Denis is a big fan of
classical music, at least twice a week he attends concerts at the
Philharmonic.
This year, Denis wants to buy tickets for the whole season at once and
even already has chosen a list of concerts, which he wants to attend. Now,
he thinks, how to buy tickets. There is an opportunity in the Philharmonic
to choose any k or more concerts and to buy a single subscription for
all of them. The cost of this subscription will be equal to the total cost
of all concerts in it but with a discount p percent. There are many
types of such subscriptions, with different k and p. In addition, for
some concerts Denis, as a student, has a discount. This discount is valid
only if he buys the ticket separately, outside the subscription.
Denis, like any other poor student, wants to attend all the concerts,
spending as little money as possible. However, he knows that there are
always more people wanting to attend a concert than the number of seats in
the Philharmonic hall. So he will not buy more than one ticket for one
concert (separately or in a subscription), even if it allows him to save
money.
Input
The first line contains integers n and m that are the number of
concerts Denis wants to attend, and a number of different subscription
types at the Philharmonic (2 ≤ n ≤ 105; 1 ≤ m ≤ 105). The i-th
of the following n lines contains integers si and di that are the
price of a ticket and the discount for students in percent at the i-th
concert (100 ≤ si ≤ 50 000; 0 ≤ di ≤
100). The j-th of the following m lines contains integers kj
and pj that are the minimum number of concerts that can be combined in
the subscription of the j-th type, and a discount for it in percent (2
≤ kj ≤ n; 1 ≤ pj ≤ 100).
Output
Output the minimum amount of money Denis has to spend to attend all the
concerts. The answer should be given with an absolute or relative error
not exceeding 10−6.
Sample
input | output |
---|
6 2
500 0
700 0
300 0
400 0
500 50
800 0
5 10
6 15
| 2680.00
|
Notes
In the example, Denis needs to buy a subscription of the first type (with
10% discount) for all concerts, except the fifth one, and to buy a ticket
for the fifth concert with a student discount of 50%.
Problem Author: Denis Dublennykh
Problem Source: Open Ural FU Personal Contest 2014