import random

N = int(input(' > '))
K = N
L = []
min_times = 0
temporary_time = 0
iterations = 1000000

for i in range(N):
	L.append(input(' > '))

for i in range(iterations):
	for i in L:
		if N <= 0 :
			break
		j = random.randint(0,2)
		k = i.split()[j]
		temporary_time += int(k)
		N -= j + 1

	if min_times == 0 or temporary_time < min_times:
		min_times = temporary_time

	temporary_time = 0
	N = K

print(min_times)
input()