Submission #93732

#	Time	Username	Problem	Language	Result	Execution time	Memory
93732		abood101	Calvinball championship (CEOI15_teams)	C++17	80 / 100	1081 ms	604 KiB

teams

#include <bits/stdc++.h>
using namespace std;
 
typedef pair<int,int > pp;
typedef long long ll;
 
int const N=1e4+2,oo=1e9,M=1e6;
ll const OO=1e18;
double const eps=1e-6,PI=acos(-1);
int mod=M+7;
 
int n,aa[N],dp[2][N][2];
 
int rec(int idx,int mx,int l){
     int &ret=dp[idx][mx][l];
     if(ret!=-1)return ret;
     if(idx==n-1)return ret=1;
     if(idx==0){
         if(aa[1]>1)return ret=(rec(idx+1,2,0)+rec(idx+1,1,1))%mod;
         return ret=rec(idx+1,1,0);
     }
     if(l)return ret=(rec(idx+1,mx,l)*1LL*mx+rec(idx+1,mx+1,l))%mod;
     else{
         if(aa[idx+1]>mx)ret=(rec(idx+1,mx,1)*1LL*mx+rec(idx+1,aa[idx+1],0))%mod;
         else ret=(rec(idx+1,mx,1)*1LL*(aa[idx+1]-1)+rec(idx+1,mx,0))%mod;
         return ret;
     }
     return ret;
 }
int main(){
    scanf("%d",&n);
    for(int i=0;i<n;i++)scanf("%d",&aa[i]);
/*    memset(dp,-1,sizeof dp);
    cout<<rec(0,0,0)<<endl;*/
    int f=0,an=0;
    for(int i=1;i<=n;i++)dp[f][i][0]=dp[f][i][1]=1;
    for(int i=n-2;i>-1;i--){
        f=1-f;
        for(int j=1;j<=n;j++){
            dp[f][j][1]=(dp[!f][j][1]*1LL*j+dp[!f][j+1][1])%mod;
            if(aa[i+1]>j)dp[f][j][0]=(dp[!f][j][1]*1LL*j+(aa[i+1]==j+1)*dp[!f][aa[i+1]][0])%mod;
            else dp[f][j][0]=(dp[!f][j][1]*1LL*(aa[i+1]-1)+dp[!f][j][0])%mod;
        }
    }
  printf("%d\n",dp[f][1][0]);
//    printf("%d\n",an);
    return 0;
}

Compilation message (stderr)

teams.cpp: In function 'int main()':
teams.cpp:35:13: warning: unused variable 'an' [-Wunused-variable]
     int f=0,an=0;
             ^~
teams.cpp:31:10: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
     scanf("%d",&n);
     ~~~~~^~~~~~~~~
teams.cpp:32:30: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
     for(int i=0;i<n;i++)scanf("%d",&aa[i]);
                         ~~~~~^~~~~~~~~~~~~

• 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: 10 / 10
• Subtask 10: 0 / 10