rt，bdfs 说是 linux 下非法指令。下面是代码

#include<bits/stdc++.h>
#define int long long
#define x first
#define y1 fhgikdjcviosjfhjglkf35754893
#define y second
#define rep(i,l,r) for(int i=l;i<=r;i++)
using namespace std;
int Hash(const string& s){
    int ans=0,fac=40320;
    rep(i,0,8){
        int cnt=0;
        rep(j,i+1,8) cnt+=(s[j]<s[i]);
        ans+=cnt*fac,fac/=8-i;
    }
    return ans;
}
signed main(){
    cout<<Hash("012345678");
}