Submission #82399

#	Time	Username	Problem	Language	Result	Execution time	Memory
82399		AngelKnows	Calvinball championship (CEOI15_teams)	C++14	20 / 100	156 ms	66560 KiB

teams

#include <bits/stdc++.h>
using namespace std;
#define FOR(i,n) for (int i=1;i<=n;i++)
#define REP(i,a,b) for (int i=a;i<=b;i++)
 
#define pb push_back
#define fi first
#define se second
#define pi pair<int,int>
#define mp make_pair
#define sz(x) ((int)(x).size())
 
typedef long long ll;

const int inf=0x3f3f3f3f;
const ll linf=1e18;
const int N=10000+1;
const double eps=1e-5;
const int mo=1e9+7;

int n;
int a[N];
int g[N][N];
int f[N][N];
int dp[N];
int pre;
int tot;
int ans;
int main() {
 
    std::ios::sync_with_stdio(false);
    cin.tie(0);
    cout.tie(0);

    //freopen("in.txt","r",stdin);
    //freopen("out.txt","w",stdout);
    scanf("%d",&n);
    FOR(i,n) scanf("%d",&a[i]);
    FOR(i,n) g[i][0]=1;
    FOR(i,n) FOR(j,n) {
    	g[i][j]=(ll)g[i][j-1]*i%mo;
	}
	FOR(i,n) f[0][i]=f[1][i]=1;
	REP(i,2,n) FOR(j,n) {
		f[i][j]=((ll)f[i-1][j+1]%mo+(ll)j*f[i-1][j]%mo)%mo;
	}
	FOR(i,n) {
		pre=tot;
		tot=max(tot,a[i]);
		if (a[i]>1) {
			if (tot==pre) FOR(j,n-i+1) dp[i]+=(ll)(a[i]-1)*g[tot][j-1]%mo*f[n-i-j+1][tot+1]%mo,dp[i]%=mo;
			else {
				FOR(j,n-i+1) dp[i]+=(ll)(a[i]-1)*g[pre][j-1]%mo*f[n-i-j+1][tot]%mo,dp[i]%=mo;
			}
		}
		//cout<<dp[i]<<endl;
		ans+=dp[i];
		ans%=mo;
	}
	ans=(ans+1)%mo;
	printf("%d\n",ans);
	return 0;
}

Compilation message (stderr)

teams.cpp: In function 'int main()':
teams.cpp:37:10: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
     scanf("%d",&n);
     ~~~~~^~~~~~~~~
teams.cpp:38:19: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
     FOR(i,n) scanf("%d",&a[i]);
              ~~~~~^~~~~~~~~~~~

• Subtask 1: 10 / 10
• Subtask 2: 10 / 10
• Subtask 3: 0 / 10
• Subtask 4: 0 / 10
• Subtask 5: 0 / 10
• Subtask 6: 0 / 10
• Subtask 7: 0 / 10
• Subtask 8: 0 / 10
• Subtask 9: 0 / 10
• Subtask 10: 0 / 10