rt，dalao 来帮忙看看。

#include <bits/stdc++.h>
using namespace std;
struct node{
	string s;
	int step;
	node(string _s,int _step):s(_s),step(_step){}
};
map<string,bool> mp;
void bfs(string s){
	queue<node> q;
	mp[s] = 1;
	q.push(node(s,0));
	while(!q.empty()){
		//找0 
		int pos;
		for(int i = 0;i < 9;i++){
			if(q.front().s[i] == '0'){
				pos = i;
				break;
			}
		}
		
		for(int i = -3;i <= 3;i+=2){
			if(pos+i < 0 || pos+i >= 9) continue;
			int k = pos+i;
			string ns = q.front().s;
			swap(ns[pos],ns[k]);
			if(!mp[ns]){
				q.push(node(ns,q.front().step+1));
				mp[ns] = 1;
				if(ns == "123804765"){
					cout<<q.back().step;
					return;
				}
			}
		}
		q.pop();
	}
}
int main(){
	string s;
	cin>>s;
	bfs(s);
	return 0;
}

剩下的都wa了