P2730中本地测试完好无损，下了数据是对的，但评测就是错的。有谁知道为什么洛谷评测时一直第一个数输出 $0$ 吗（）

12pts.

#include<bits/stdc++.h>
using namespace std;
string mb = "";
map<string,string>a;
string Id1(string s){
	string r = "";
	for(int i = 7;i>=4;i--){
		r+=s[i];
	}
	for(int i = 3;i>=0;i--){
		r+=s[i];
	}
	return r;
}
string Id2(string s){
	string r = "";
	r+=s[3];
	r+=s[0];
	r+=s[1];
	r+=s[2];
	r+=s[5];
	r+=s[6];
	r+=s[7];
	r+=s[4];
	return r;
}
string Id3(string s){
	string r = "";
	r+=s[0];
	r+=s[6];
	r+=s[1];
	r+=s[3];
	r+=s[4];
	r+=s[2];
	r+=s[5];
	r+=s[7];
	return r;
}
void bfs(string start){
	a[start] = "";
	queue<string>x;
	x.push(start);
	while(!x.empty()){
		//cout<<"start:"<<x.front()<<endl;
		if(x.front()==mb){
			return;
		}
		if(a[Id1(x.front())]==""){
			//cout<<"Type 1 Push in:"<<Id1(x.front())<<endl;
			x.push(Id1(x.front()));
			a[Id1(x.front())] = a[x.front()]+'A';
		}
		if(a[Id2(x.front())]==""){
			//cout<<"Type 2 Push in:"<<Id2(x.front())<<endl;
			x.push(Id2(x.front()));
			a[Id2(x.front())] = a[x.front()]+'B';
		}
		if(a[Id3(x.front())]==""){
			//cout<<"Type 3 Push in:"<<Id3(x.front())<<endl;
			x.push(Id3(x.front()));
			a[Id3(x.front())] = a[x.front()]+'C';
		}
		x.pop();
	}
}
int main(){
	string mbh;
	getline(cin,mbh);
	for(int i = 0;i<mbh.length();i++){
		if(mbh[i]!=' ')mb+=mbh[i];
	}
	//cout<<mb<<endl;
//	cout<<Id1("12345678")<<endl;
//	cout<<Id2("12345678")<<endl;
//	cout<<Id3("12345678")<<endl;
	//a["000000"] = "789";
	//cout<<(a.find("000000"))<<endl; 
	bfs("12345678");
	cout<<a[mb].length()<<endl;
	cout<<a[mb]<<endl;
	//return 0;
	system ("pause");
}

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