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 int long long
#define ll long long
#define mp make_pair
#define pb push_back
#define eb emplace_back
#define pii pair<ll,ll>
#define vpii vector<pair<ll,ll> >
#define F first
#define S second
#define ld long double
#define built __builtin_popcountll
#define mst(a,i) memset(a,i,sizeof(a))
#define all(x) x.begin(),x.end()
#define itit(it,a) for(auto it=(a).begin(); it!=(a).end(); it++)
#define rep(i,a,b) for(ll i=a; i<b; i++)
#define repr(i,a,b) for(ll i=a; i>b; i--)
#define reprr(i,a,b) for(ll i=a; i>=b; i--)
#define pi 3.14159265358979323846264338327950288419716939937510582097494459230
ll max3(ll x,ll y,ll z) {return max(max(x,y),z);}
ll min3(ll x,ll y,ll z) {return min(min(x,y),z);}
const ll N=1e5+10,M=2e5+10,M2=1e6+10,mod=1e9+7,inf=1e17+10;
const int INF=1e9+7;
void add(int& a, int b) {a+=b;if(a>=mod){a-=mod;}}

#define trace(...) cerr<<"Line:"<<__LINE__<<" "; __f(#__VA_ARGS__, __VA_ARGS__)
template<typename Arg1>
void __f(const char *name, Arg1 &&arg1) {
    cerr<<name<<" : "<<arg1<<endl;
}
template<typename Arg1, typename ... Args>
void __f(const char *names, Arg1 &&arg1, Args &&... args) {
    const char *comma=strchr(names+1,',');
    cerr.write(names,comma-names)<<" : "<<arg1<<" | ";
    __f(comma+1,args...);
}

int X[] = {0, 1, 0, -1};
int Y[] = {-1, 0, 1, 0};
//assic value of ('0'-'9') is(48 - 57) and (a-z) is (97-122) and (A-Z) is(65-90) and 32 for space
ll power(ll x,ll n){ll result=1;while(n>0){if(n%2==1)result=(result*x)%mod; x=((x%mod)*(x%mod))%mod;n=n/2;}return result;}


int32_t main()
{
    ios::sync_with_stdio(0);
    cin.tie(0);
    cout.tie(0);
    bool a=false,b=false;
    string s;
    cin >> s;
    rep(i,0,s.size()){
        if(s[i]=='A') a=true;
        else b=true;
    }
    if(a && b) cout << "Yes";
    else cout << "No";
    return 0;
}