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 C++14 (GCC 5.4.1) (judge verdict: Accepted)

#include <bits/stdc++.h>
#define _USE_MATH_DEFINES
#include <math.h>
#include <algorithm>
#define rep(i, n) for (int i = 0; i < (n); ++i)
#define all(x) x.begin(), x.end()
#define rall(x) x.rbegin(), x.rend()
#define acc(v) accumulate(v.begin(), v.end(), 0)

using namespace std;
typedef long long ll;
const int INF = 1e9;
const ll LINF = 1e18;
const ll MOD = 1e9 + 7;

int main()
{
	string s;
	cin >> s;
	cout << (s[0] == s[1] && s[1] == s[2] ? "No" : "Yes") << endl;
}