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>
using namespace std;
#define _GLIBCXX_DEBUG
#define rep2(i, m, n) for(int i=int(m); i<int(n); i++)
#define rep(i, n) rep2(i, 0, n)
#define ALL(a) a.begin(), a.end()
using ll = long long;
using ld = long double;
using V = vector<int>;
using Vll = vector<ll>;
using Vld = vector<ld>;
using VV = vector<V>;
using VVll = vector<Vll>;
using VVld = vector<Vld>;
using P = pair<int, int>;
using Pll = pair<ll, ll>;
using Pld = pair<ld, ld>;
const ll INF = ll(1e15)+10;
const ld EPS = 1e-10;
const int MOD = int(1e9)+7;

int main() {
	string S;
	cin >> S;
	int numA = 0;
	int numB = 0;
	rep(i, S.size()) {
		if (S[i] == 'A') numA++;
		if (S[i] == 'B') numB++;
	}
	if (numA > 0 && numB > 0) cout << "Yes";
	else cout << "No";
	cout << endl;
	return 0;
}