#include "bits/stdc++.h"

#define REP(i,n) for(ll i=0;i<n;++i)
#define RREP(i,n) for(ll i=n-1;i>=0;--i)
#define FOR(i,m,n) for(ll i=m;i<n;++i)
#define RFOR(i,m,n) for(ll i=n-1;i>=m;--i)
#define ALL(v) (v).begin(),(v).end()
#define UNIQUE(v) v.erase(unique(ALL(v)),v.end());
#define DUMP(v) REP(aa, (v).size()) { cout << v[aa]; if (aa != v.size() - 1)cout << " "; else cout << endl; }
#define INF 1000000001ll
#define MOD 1000000007ll
#define EPS 1e-9

const int dx[8] = { 1,1,0,-1,-1,-1,0,1 };
const int dy[8] = { 0,1,1,1,0,-1,-1,-1 };


using namespace std;
typedef long long ll;
typedef vector<int> vi;
typedef vector<ll> vl;
typedef vector<vi> vvi;
typedef vector<vl> vvl;
typedef pair<int, int> pii;
typedef pair<ll, ll> pll;
ll max(ll a, int b) { return max(a, ll(b)); }
ll max(int a, ll b) { return max(ll(a), b); }
ll min(ll a, int b) { return min(a, ll(b)); }
ll min(int a, ll b) { return min(ll(a), b); }
///(?´????????`)(?´????????`)(?´????????`)(?´????????`)(?´????????`)(?´????????`)///

int main() {
	cin.tie(0);
	ios::sync_with_stdio(false);
	string s;
	cin >> s;
	if (s.size() == 1) {
		cout << "No" << endl;
	}
	else {
		int flag = 0;
		while (1) {
			string tmp = s;
			vi cnt(3, 0);
			REP(i, tmp.size()) {
				cnt[tmp[i] - 'A']++;
			}
			char c = min_element(ALL(cnt))-cnt.begin() + 'A';
			int b = 0;
			REP(i, 3)if (cnt[i] == *min_element(ALL(cnt)))b++;
			if (b != 1)break;
			for (int i = 0; i + 2 < tmp.size(); ++i) {
				if (tmp.substr(i, 3) == "ABC") {
					tmp[i] = c;
					tmp.erase(tmp.begin() + i + 1);
					tmp.erase(tmp.begin() + i + 1);
				}
			}
			if (s == tmp)break;
			s = tmp;
		}
		if (s!="ABC")cout << "No" << endl;
		else cout << "Yes" << endl;
	}
}