WA求助

#include<bits/stdc++.h>
using namespace std;
int m,n,f[6]={10,5,1,-10,-5,-1},vd[114];
queue<pair<int,int> >q; 
void bfs(int a,int step){
	pair<int,int>p;
	q.push(make_pair(a,step));
	vd[a]++;
	while(!q.empty()){
		p=q.front();
		q.pop();
		if(p.first==m){
			cout<<p.second;
			return ;
		}
		for(int i=0;i<6;i++){
			int ba=p.first+f[i];
			if(ba>=0&&vd[ba]==0){
				q.push(make_pair(ba,p.second+1));
				vd[ba]++;
			}
		}
	}
}
int main(){
	cin>>n>>m;
	bfs(n,0);
	return 0;
}