Submission #1062615

#	Time	Username	Problem	Language	Result	Execution time	Memory
1062615		12345678	Amusement Park (CEOI19_amusementpark)	C++17	19 / 100	106 ms	10836 KiB

amusementpark

#include <bits/stdc++.h>

using namespace std;

#define ll long long

const int nx=11, mx=1e3+5, mod=998244353, mod2=1e9+7;

ll n, m, a[mx], b[mx], res, pw[mx];
set<ll> s;

int main()
{
    cin.tie(NULL)->sync_with_stdio(false);
    cin>>n>>m;
    pw[0]=1;
    for (int i=1; i<=m; i++) pw[i]=(pw[i-1]*2)%mod2;
    for (int i=1; i<=m; i++) cin>>a[i]>>b[i];
    vector<int> v;
    for (int i=1; i<=n; i++) v.push_back(i);
    do
    {
        ll sm=0, cnt=0;
        for (int i=1; i<=m; i++) if (v[a[i]-1]>v[b[i]-1]) cnt++, sm=(sm+pw[i])%mod2;
        if (s.find(sm)==s.end()) res=(res+cnt)%mod, s.insert(sm);
    } while (next_permutation(v.begin(), v.end()));
    cout<<res;
}

• Subtask 1: 7 / 7
• Subtask 2: 12 / 12
• Subtask 3: 0 / 23
• Subtask 4: 0 / 21
• Subtask 5: 0 / 37