Submission #448031

#	Time	Username	Problem	Language	Result	Execution time	Memory
448031		minoum	Calvinball championship (CEOI15_teams)	C++17	70 / 100	738 ms	32172 KiB

teams

#include<bits/stdc++.h>
 
using namespace std;
typedef long long int ll;
 
const int MAXN = 1005;
const ll md = 1e6+7;
 
ll n, a[MAXN], pt = 0;
ll ans = 0;
map <pair<int,int>,ll> dp;

void get(int sz, int t){
	if(dp[{sz,t}]) return;
	if(sz==0){
		dp[{sz,t}] = 1ll;
		return;
	}
	get(sz-1,t); get(sz-1,t+1);
	dp[{sz,t}] = (((ll)t*dp[{sz-1,t}])%md)+dp[{sz-1,t+1}]; 
	dp[{sz,t}] = (dp[{sz,t}]>=md?dp[{sz,t}]-md:dp[{sz,t}]);
	/*for(int i = 1; i < MAXN; i++) dp[1][i] = i+1, dp[0][i] = 1ll;
	for(ll i = 2; i < MAXN; i++)
		for(ll j = 1; j < MAXN; j++){
			dp[i][j] = (j*dp[i-1][j])%md;
			if(j+1 < MAXN) dp[i][j] += dp[i-1][j+1], dp[i][j] = (dp[i][j]>=md?dp[i][j]-md:dp[i][j]);
		}*/
	return;
}
 
int32_t main()
{
	ios_base::sync_with_stdio(false); cin.tie(0); cout.tie(0);
	cin >> n;
	for(int i = 0; i < n; i++) cin >> a[i];
	pt = 1;
	for(int i = 0; i < n; i++){
		if(a[i]==1) continue;
		ll tmp = (ll)a[i]-1ll;
		get(n-i+1,pt);
		tmp = (tmp*dp[{n-i-1,pt}])%md;
		ans = (ans+tmp)%md;
		if(a[i]==pt+1) pt++;
	}
	cout << (ans+1)%md << '\n';
	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: 0 / 10
• Subtask 9: 0 / 10
• Subtask 10: 0 / 10