codeforces#1090 D. New Year and the Permutation Concatenation（打表找规律）

#include<bits/stdc++.h>
using namespace std;
#define ll long long
const int maxn=6e5+10;
int num[maxn];
vector<int>ve;
int main()
{
    int k=8;
    while(k--)
    {
        ve.clear();
        cout<<k<<" ";
        for(int i=0; i<maxn; i++)
            num[i]=i;
        do
        {
            for(int i=1; i<=k; i++)
                ve.push_back(num[i]);
        }
        while(next_permutation(num+1,num+k+1));
        int ans=0;
        for(int i=0; i<ve.size(); i++)
        {
            for(int j=i; j<ve.size(); j++)
            {
                if(j-i+1!=k)continue;
                ll cal=0;
                for(int l=i; l<=j; l++)
                    cal+=ve[l];
                if(cal==(k+1)*k/2)
                    ans++;
            }
        }
        cout<<ans<<endl;
    }

    return 0;
}