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 fast ios_base::sync_with_stdio(false);cin.tie(NULL);cout.tie(NULL);
#define deb1(x) cout<<#x<<" :: "<<x<<"\n";
#define deb2(x,y) cout<<#x<<" :: "<<x<<"\t"<<#y<<" :: "<<y<<"\n";
#define deb3(x,y,z) cout<<#x<<" :: "<<x<<"\t"<<#y<<" :: "<<y<<"\t"<<#z<<" :: "<<z<<"\n";
#define lli long long int
#define pii pair<lli,lli>
#define f first
#define sE second
lli n,x,y,t,mod=1e9+7,ans=0; 
int main() { 
    fast
    string s;
    cin>>s;
    if(s[0]!=s[1] || s[1]!=s[2] || s[0]!=s[2])
        cout<<"Yes"<<endl;
    else
        cout<<"No"<<endl;
        
}