#5 WA, 求助

#include<bits/stdc++.h>
#define int long long
using namespace std;

int a,b;
queue<int> q;
int step[105];

void solve(){
    cin >> a >> b;
    if(a == b){
        cout << 0;
        return;
    }
    memset(step,-1,sizeof(step));
    q.push(a);
    step[a] = 0;
    while(!q.empty()){
        int last = q.front();
        q.pop();
        int adjust[5] = {1,5,10};
        for(int i=0;i<3;i++){
            if(step[last+adjust[i]] == -1){
                step[last+adjust[i]] = step[last]+1;
                if(last+adjust[i] == b){
                    cout << step[last+adjust[i]] << endl;
                    return;
                }
                q.push(last+adjust[i]);
            }
            if(step[last-adjust[i]] == -1){
                step[last-adjust[i]] = step[last]+1;
                if(last-adjust[i] == b){
                    cout << step[last-adjust[i]] << endl;
                    return;
                }
                q.push(last-adjust[i]);
            }
        }
    }
}

signed main(){
    ios::sync_with_stdio(0);
    cin.tie(0);
    cout.tie(0);
    solve();
    return 0;
}

求dalao指教，谢谢