ship_battle_matrix

n = int(input())

all_ships = []
for iterations in range(1, n+1):
    field = [list(map(int,input().split()))]
    all_ships += field

attacked = input().split(" ")

destroyed = 0
for shot in range(len(attacked)):
    current_attack = attacked[shot]
    row = int(current_attack[0])
    col = int(current_attack[2])
    all_ships[row][col] -= 1

    if all_ships[row][col] == 0:
        destroyed += 1

print(destroyed)