Book Club [Rob Kolstad, 2010]

Bessie is looking for cows to join her book club. While the herd
has N (2 <= N <= 50,000) cows conveniently numbered 1..N, she wants
only the most discerning and social cows for her book club.

Thus, like a dating service, she has created a questionnaire and
asked each of the N cows to complete its NQ (1 <= NQ <= 50) questions
(named R_1..R_NQ). These are questions like "How much do you enjoy
reading science fiction?" and each answer is an integer in the range
1..5.

Your job is to tabulate the questionnaire's results and answer a
simple question like: "How many cows answered 2 to question 3, 4
to question 7, and also 1 to question 8?"  The question has P parts
(1 <= P <= 10), and each part has Qj (1 <= Qj <= NQ) and Aj (1 <=
Aj <= 5), respectively the question number and the required answer.
Your program prints a single integer that is the total number of
cows that answered Aj to Qj for j in the range 1..P.

Consider a small herd of just 4 cows and a small questionnaire of
just 5 questions; the responses are:

Cow     Question
 ID   1  2  3  4  5
 1    1  1  1  1  1
 2    1  2  3  4  5
 3    1  2  1  2  3
 4    2  1  1  2  2

If the tabulation question was "How many cows answered 2 to question
1 and 1 to question 2?" the answer would be 1 (just cow #4). If the
tabulation question was "How many cows answered 1 to question 1 and
1 to question 3?" the answer would be 2 (cows 1 and 3).

PROBLEM NAME: bookclub

INPUT FORMAT:

* Line 1: Three space-separated integers: N, NQ, and P

* Lines 2..N+1: Line i+1 contains NQ space-separated integers that are
        the response to the questions for cow i: R_1..R_NQ

* Lines N+2..N+1+P: Line j+N+1 contains two space-separated integers:
        Qj and Aj

SAMPLE INPUT (file bookclub.in):

4 5 2
1 1 1 1 1
1 2 3 4 5
1 2 1 2 3
2 1 1 2 2
1 1
3 1

OUTPUT FORMAT:

* Line 1: A single integer that is the number of cows that meet all of
        Bessie's criteria

SAMPLE OUTPUT (file bookclub.out):

2