求调今晚AT T2的代码，玄关

#include<bits/stdc++.h>
using namespace std;
const int maxsize = 1e4;
const int maxn = 1e8;
const int INF = 0x3f3f3f3f;
const int mod = 1e6+7;
string s;
bool p,q,k;
int main(){
	cin >> s;
	for(int i = 1;i <= s.size();i++){
		if(p && s[i] == 'A'){
			cout << "No";
			return 0;
		}
		if(q && s[i] == 'B'){
			cout << "No";
			return 0;
		}
		if(k && s[i] == 'C'){
			cout << "No";
			return 0;
		}
		if(s[i] != s[i - 1]){
			if(s[i - 1] - '0' > s[i] - '0'){
				cout << "No";
				return 0;
			}
			if(s[i - 1] == 'A') p = 1;
			if(s[i - 1] == 'B') q = 1;
			if(s[i - 1] == 'C') k = 1;
		}
	}
	cout << "Yes";
	return 0;
}