Problem:
Score : 100 points

Problem Statement

In AtCoder City, there are three stations numbered 1, 2, and 3.

Each of these stations is operated by one of the two railway companies, A and B. A string S of length 3 represents which company operates each station. If S_i is A, Company A operates Station i; if S_i is B, Company B operates Station i.

To improve the transportation condition, for each pair of a station operated by Company A and one operated by Company B, there will be a bus service connecting them.

Determine if there is a pair of stations that will be connected by a bus service.

Constraints

Each character of S is A or B.

|S| = 3

Input

Input is given from Standard Input in the following format:

S

Output

If there is a pair of stations that will be connected by a bus service, print Yes; otherwise, print No.

Sample Input 1

ABA

Sample Output 1

Yes

Company A operates Station 1 and 3, while Company B operates Station 2.

There will be a bus service between Station 1 and 2, and between Station 2 and 3, so print Yes.

Sample Input 2

BBA

Sample Output 2

Yes

Company B operates Station 1 and 2, while Company A operates Station 3.

There will be a bus service between Station 1 and 3, and between Station 2 and 3, so print Yes.

Sample Input 3

BBB

Sample Output 3

No

Company B operates all the stations. Thus, there will be no bus service, so print No.

Solution in Ruby (2.3.3) (judge verdict: Wrong Answer)

str = ["0"]
s = gets.to_s.chomp
q = gets.to_i
# print str
# print q
ret = 0

q.times do |i|
  arr = gets.split(' ').to_a
  if arr[0] == "1"
    ret += 1
  elsif ((arr[1] == "1") && (ret % 2 == 0)) || ((arr[1] == "2") && (ret % 2 == 1))
      str.unshift(arr[2])
  else
    str.push(arr[2])
  end
end

n = str.index("0")

if ret % 2 == 0
  str[n] = s
else
  str[n] = s.reverse
  str.reverse!
end

print(str.join(''))