题解 | 买橘子

#include<bits/stdc++.h>
using namespace std;
#define int long long
typedef pair<int,int>P;
const int N=1e6+7;
int a[N],b[N];
void run(){
    int n;
    cin>>n;
    int val=n/8;
    int ans=(n-n/8*8);
    if(ans%6==0){
        cout<<n/8+ans/6;
    }else{
        while(ans%6!=0 && val>=0){
            val--;
            ans+=8;
        }
        if(ans%6!=0){
            cout<<-1;
        }else{
            cout<<val+ans/6;
        }
    }
}
signed main(){
    ios::sync_with_stdio(false);
    cin.tie(0),cout.tie(0);
    // int t;cin>>t;while(t--)
    run();
    return 0;
}