#include <bits/stdc++.h>
#include <numeric>
// #include <atcoder/modint>

using namespace std;
// using namespace atcoder;

// using mint = modint998244353;

#define i64 int_fast64_t

const i64 INF = INT64_MAX;

const i64 ERR = INT64_MIN;

const i64 MOD = 998244353;

// 切り上げ
i64 ceil_devide(i64 x, i64 y) {
    return (x + y - 1) / y;
}

// 切り捨て
i64 floor_devide(i64 x, i64 y) {
    return x / y;
}

i64 sum_linear(i64 n) {
    return n * (n+1) / 2;
}

int main()
{
    string s;
    cin >> s;

    if (s.at(0) == s.at(1) && s.at(1) != s.at(2)) {
        cout << "Yes" << endl;
    } else {
        cout << "No" << endl;
    }



    return 0;
}