In this problem, we consider a simple programming language that has only declarations of one- dimensional integer arrays and assignment statements. The problem is to find a bug in the given program.

The syntax of this language is given in BNF as follows:

<image>

where <new line> denotes a new line character (LF).

Characters used in a program are alphabetical letters, decimal digits, =, [, ] and new line characters. No other characters appear in a program.

A declaration declares an array and specifies its length. Valid indices of an array of length n are integers between 0 and n - 1, inclusive. Note that the array names are case sensitive, i.e. array a and array A are different arrays. The initial value of each element in the declared array is undefined.

For example, array a of length 10 and array b of length 5 are declared respectively as follows.


a[10]
b[5]


An expression evaluates to a non-negative integer. A <number> is interpreted as a decimal integer. An <array_name> [<expression>] evaluates to the value of the <expression> -th element of the array. An assignment assigns the value denoted by the right hand side to the array element specified by the left hand side.

Examples of assignments are as follows.


a[0]=3
a[1]=0
a[2]=a[a[1]]
a[a[0]]=a[1]


A program is executed from the first line, line by line. You can assume that an array is declared once and only once before any of its element is assigned or referred to.

Given a program, you are requested to find the following bugs.

* An index of an array is invalid.
* An array element that has not been assigned before is referred to in an assignment as an index of array or as the value to be assigned.



You can assume that other bugs, such as syntax errors, do not appear. You can also assume that integers represented by <number>s are between 0 and 231 - 1 (= 2147483647), inclusive.



Input

The input consists of multiple datasets followed by a line which contains only a single '.' (period). Each dataset consists of a program also followed by a line which contains only a single '.' (period). A program does not exceed 1000 lines. Any line does not exceed 80 characters excluding a new line character.

Output

For each program in the input, you should answer the line number of the assignment in which the first bug appears. The line numbers start with 1 for each program. If the program does not have a bug, you should answer zero. The output should not contain extra characters such as spaces.

Example

Input

a[3]
a[0]=a[1]
.
x[1]
x[0]=x[0]
.
a[0]
a[0]=1
.
b[2]
b[0]=2
b[1]=b[b[0]]
b[0]=b[1]
.
g[2]
G[10]
g[0]=0
g[1]=G[0]
.
a[2147483647]
a[0]=1
B[2]
B[a[0]]=2
a[B[a[0]]]=3
a[2147483646]=a[2]
.
.


Output

2
2
2
3
4
0

Difficulty: UNKNOWN_DIFFICULTY

Starter code:

Solutions:
import re

def deref(d, expr):
	expr = expr.replace(']', '')
	symb = expr.split('[')
	symb[-1] = symb[-1]
	while len(symb) > 1:
		(name, index) = symb[-2:]
		if index not in d[name]:
			return None
		symb.pop()
		symb.pop()
		symb.append(d[name][index])
	return symb[0]

def check(s):
	d = {}
	dd = {}
	for (i, stmt) in enumerate(s, 1):
		if '=' not in stmt:
			name = stmt[0]
			index = stmt[2:-1]
			d[name] = {}
			dd[name] = int(index)
			continue
		(lhs, rhs) = stmt.split('=')
		name = lhs[0]
		index = lhs[2:-1]
		index = deref(d, index)
		value = deref(d, rhs)
		if index is None or value is None or int(index) >= dd[name]:
			print(i)
			return
		d[name][index] = value
	print(0)

def main():
	list_ = []
	with open(0) as fin:
		for line in fin:
			line = line.strip()
			if line == '.':
				if not list_:
					return 0
				check(list_)
				list_ = []
				continue
			list_.append(line)
main()


class CustomArray:

	def __init__(self, sz):
		self.sz = sz
		self.vals = {}

	def size(self):
		return self.sz

	def assign(self, idx, val):
		if idx == None or val == None:
			return False
		if idx >= self.sz:
			return False
		self.vals[idx] = val
		return True

	def get(self, idx):
		if idx == None:
			return None
		if idx >= self.sz:
			return None
		if idx not in self.vals:
			return None
		return self.vals[idx]

class Arrays:

	def __init__(self):
		self.arrays = {}

	def declare(self, arrName, sz):
		if sz == None:
			return False
		if arrName in self.arrays:
			return False
		self.arrays[arrName] = CustomArray(sz)
		return True

	def assign(self, arrName, idx, val):
		if arrName not in self.arrays:
			return False
		return self.arrays[arrName].assign(idx, val)

	def get(self, arrName, idx):
		if arrName not in self.arrays:
			return None
		return self.arrays[arrName].get(idx)

def resolve(expression):
	global arrays
	if '[' not in expression:
		return int(expression)
	arrName = expression[0]
	idx = resolve(expression[2:-1])
	return arrays.get(arrName, idx)

def processAssignment(command):
	global arrays
	equalIdx = command.find('=')
	leftStr = command[:equalIdx]
	rightStr = command[equalIdx + 1:]
	leftArrName = leftStr[0]
	leftIdx = resolve(leftStr[2:-1])
	rhs = resolve(rightStr)
	return arrays.assign(leftArrName, leftIdx, rhs)

def processDeclaration(arrStr):
	global arrays
	arrName = arrStr[0]
	sz = int(arrStr[2:-1])
	return arrays.declare(arrName, sz)
while True:
	commands = []
	while True:
		line = input().strip()
		if line == '.':
			break
		commands.append(line)
	if len(commands) == 0:
		break
	errLine = 0
	arrays = Arrays()
	for i in range(len(commands)):
		command = commands[i]
		if '=' in command:
			result = processAssignment(command)
		else:
			result = processDeclaration(command)
		if not result:
			errLine = i + 1
			break
	print(errLine)


import re

def get_value(expr, array_size, array):
	seq = expr.replace(']', '').split('[')
	seq[-1] = int(seq[-1])
	while len(seq) > 1:
		ind = seq.pop()
		arr = seq.pop()
		if arr not in array or ind not in array[arr]:
			raise KeyError
		seq.append(array[arr][ind])
	return seq[0]

def testcase_ends():
	array_size = {}
	array = {}
	decl_prog = re.compile('(\\w)\\[(\\d+)\\]')
	line = input().strip()
	if line == '.':
		return True
	i = 1
	while True:
		if line == '.':
			print(0)
			return False
		if '=' in line:
			(lhs, rhs) = line.split('=')
			name = lhs[0]
			try:
				ind = get_value(lhs[2:-1], array_size, array)
				value = get_value(rhs, array_size, array)
				if name not in array or ind >= array_size[name]:
					raise KeyError
				array[name][ind] = value
			except KeyError:
				print(i)
				break
		else:
			m = decl_prog.fullmatch(line)
			assert m is not None
			name = m.group(1)
			size = int(m.group(2))
			array_size[name] = size
			array[name] = {}
		line = input().strip()
		i += 1
	line = input().strip()
	while line != '.':
		line = input().strip()
	return False
while not testcase_ends():
	pass


import math, string, itertools, fractions, heapq, collections, re, array, bisect, sys, random, time, copy, functools
sys.setrecursionlimit(10 ** 7)
inf = 10 ** 20
eps = 1.0 / 10 ** 13
mod = 10 ** 9 + 7
dd = [(-1, 0), (0, 1), (1, 0), (0, -1)]
ddn = [(-1, 0), (-1, 1), (0, 1), (1, 1), (1, 0), (1, -1), (0, -1), (-1, -1)]

def LI():
	return [int(x) for x in sys.stdin.readline().split()]

def LI_():
	return [int(x) - 1 for x in sys.stdin.readline().split()]

def LF():
	return [float(x) for x in sys.stdin.readline().split()]

def LS():
	return sys.stdin.readline().split()

def I():
	return int(sys.stdin.readline())

def F():
	return float(sys.stdin.readline())

def S():
	return input()

def pf(s):
	return print(s, flush=True)

def main():
	rr = []

	def f(n):
		_a = [n]
		while 1:
			s = S()
			if s == '.':
				break
			_a.append(s)
		_ks = {}
		_d = {}
		for _i in range(len(_a)):
			_s = _a[_i]
			if '=' in _s:
				try:
					exec(_s, _d)
					for _k in _ks.keys():
						_kl = _d[_k].keys()
						if _kl and max(_kl) >= _ks[_k]:
							return _i + 1
				except:
					return _i + 1
			else:
				_k = _s.split('[')[0]
				_n = int(_s.split('[')[1].split(']')[0])
				_ks[_k] = _n
				if _n < 1:
					continue
				exec(_k + '={}', _d)
		return 0
	while 1:
		n = S()
		if n == '.':
			break
		rr.append(f(n))
	return '\n'.join(map(str, rr))
print(main())