import sys
from collections import deque
D = { ">":"<", ")":"(", "]":"[","}":"{", }
S = { "(":1, "[":2, "{":3, "<":4, }
L = sys.stdin.read().splitlines()
N = []
for l in L:
	Q = deque(["y"]) # add buffer to pop
	fail = False
	for c in l:
		p = Q.pop()
		if c in D:  # if closing char
			e = D[c]
			if p != e: # fail case
				fail = True
				break
			else: # just discard the pair
				pass
		else:  # not closing
			Q.append(p)
			Q.append(c)
	if not fail:
		R = list(Q)[1:]
		s = 0
		for r in reversed(R):
			s = s*5 + S[r]
		N.append(s)
print(sorted(N)[len(N)//2])