Submission #1081643

#	Time	Username	Problem	Language	Result	Execution time	Memory
1081643		Victor	Calvinball championship (CEOI15_teams)	C++17	100 / 100	344 ms	1668 KiB

teams

// #pragma GCC target ("avx,avx2,fma")
// #pragma GCC optimize ("Ofast,inline") // O1 - O2 - O3 - Os - Ofast
// #pragma GCC optimize ("unroll-loops")
#include <bits/stdc++.h>

using namespace std;

#define rep(i, a, b) for (ll i = (a); i < (b); ++i)
#define per(i, a, b) for (ll i = (b) - 1; i >= (a); --i)
#define trav(a, x) for (auto &a : x)

#define all(x) x.begin(), x.end()
#define sz(x) (ll)x.size()
#define pb push_back
#define debug(x) cout<<#x<<" = "<<x<<endl

#define umap unordered_map
#define uset unordered_set

typedef pair<int, int> ii;
typedef pair<int, ii> iii;
typedef vector<int> vi;
typedef vector<ii> vii;
typedef vector<vi> vvi;

typedef long long ll;
typedef pair<ll,ll> pll;
typedef pair<ll,pll> ppll;
typedef vector<ll> vll;
typedef vector<pll> vpll;
typedef vector<vll> vvll;

const ll INF = 1'000'007;

int main() {
    cin.tie(0)->sync_with_stdio(0);
    cin.exceptions(cin.failbit);

    ll n;
    cin>>n;
    vll order(n);
    rep(i,0,n) cin>>order[i];

    vector<vll> dp(n+1,vll(2,0)),dp2(n+1,vll(2,0));
    dp[0][1]=1;
    rep(i,0,n) {
        rep(j,0,i+1) {
            dp2[j][0]=(dp2[j][0]+dp[j][0]*j)%INF;
            dp2[j+1][0]=(dp2[j+1][0]+dp[j][0])%INF;

            if(j+1==order[i]) dp2[j+1][1]=(dp2[j+1][1]+dp[j][1])%INF;
            else dp2[j][1]=(dp2[j][1]+dp[j][1])%INF;
            dp2[j][0]=(dp2[j][0]+dp[j][1]*(order[i]-1))%INF;

            dp[j][0]=0;
            dp[j][1]=0;
        }

        dp.swap(dp2);
    }

    ll ans=0;
    rep(i,0,n+1) rep(j,0,2) ans=(ans+dp[i][j])%INF;
    cout<<ans<<endl;
    return 0;
}

• Subtask 1: 10 / 10
• Subtask 2: 10 / 10
• Subtask 3: 10 / 10
• Subtask 4: 10 / 10
• Subtask 5: 10 / 10
• Subtask 6: 10 / 10
• Subtask 7: 10 / 10
• Subtask 8: 10 / 10
• Subtask 9: 10 / 10
• Subtask 10: 10 / 10