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Submission #47975

# Submission time Handle Problem Language Result Execution time Memory
47975 2018-05-09T09:44:58 Z Extazy Calvinball championship (CEOI15_teams) C++17
100 / 100
 137 ms 1096 KB 
#include <bits/stdc++.h>
#define endl '\n'

using namespace std;

const int N = 10007;
const int MOD = (1e6) + 7;

int n,a[N],pos,cnt;
int dp[2][N];
int state_cnt[N],state_coef[N];
long long ans;

int main() {
  ios_base::sync_with_stdio(false);
  cin.tie(NULL);
  int i;

  scanf("%d", &n);
  for(i=1;i<=n;i++) {
    scanf("%d", &a[i]);
  }

  ans=1;

  cnt=1;
  for(pos=2;pos<=n;pos++) {
    if(a[pos]>cnt) {
      state_cnt[pos]=cnt;
      state_coef[pos]=cnt;
      
      ++cnt;
    }
    else {
      state_cnt[pos]=cnt;
      state_coef[pos]=a[pos]-1;
    }
  }

  for(cnt=0;cnt<=n;cnt++) {
    dp[(n+1)&1][cnt]=1;
  }
  for(pos=n;pos>=2;pos--) {
    ans+=dp[(pos+1)&1][state_cnt[pos]]*1ll*state_coef[pos]%MOD;
    for(cnt=1;cnt<pos;cnt++) {
      dp[pos&1][cnt]=(dp[(pos+1)&1][cnt+1]+dp[(pos+1)&1][cnt]*1ll*cnt)%MOD;
    }
  }
  
  ans%=MOD;
  printf("%lld\n", ans);

  return 0;
}

Compilation message

teams.cpp: In function 'int main()':
teams.cpp:19:8: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   scanf("%d", &n);
   ~~~~~^~~~~~~~~~
teams.cpp:21:10: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
     scanf("%d", &a[i]);
     ~~~~~^~~~~~~~~~~~~

Subtask #1
10.0 / 10.0

# Verdict Execution time Memory Grader output
1 Correct 2 ms 376 KB Output is correct
2 Correct 2 ms 376 KB Output is correct
3 Correct 2 ms 408 KB Output is correct
4 Correct 2 ms 484 KB Output is correct
5 Correct 2 ms 560 KB Output is correct
6 Correct 2 ms 560 KB Output is correct

Subtask #2
10.0 / 10.0

# Verdict Execution time Memory Grader output
1 Correct 2 ms 560 KB Output is correct
2 Correct 2 ms 560 KB Output is correct
3 Correct 2 ms 616 KB Output is correct

Subtask #3
10.0 / 10.0

# Verdict Execution time Memory Grader output
1 Correct 2 ms 620 KB Output is correct
2 Correct 2 ms 620 KB Output is correct
3 Correct 2 ms 620 KB Output is correct

Subtask #4
10.0 / 10.0

# Verdict Execution time Memory Grader output
1 Correct 2 ms 636 KB Output is correct

Subtask #5
10.0 / 10.0

# Verdict Execution time Memory Grader output
1 Correct 2 ms 636 KB Output is correct
2 Correct 2 ms 636 KB Output is correct
3 Correct 2 ms 636 KB Output is correct

Subtask #6
10.0 / 10.0

# Verdict Execution time Memory Grader output
1 Correct 2 ms 636 KB Output is correct
2 Correct 2 ms 636 KB Output is correct
3 Correct 2 ms 636 KB Output is correct

Subtask #7
10.0 / 10.0

# Verdict Execution time Memory Grader output
1 Correct 3 ms 636 KB Output is correct
2 Correct 3 ms 636 KB Output is correct
3 Correct 3 ms 636 KB Output is correct

Subtask #8
10.0 / 10.0

# Verdict Execution time Memory Grader output
1 Correct 136 ms 836 KB Output is correct

Subtask #9
10.0 / 10.0

# Verdict Execution time Memory Grader output
1 Correct 29 ms 836 KB Output is correct
2 Correct 32 ms 836 KB Output is correct
3 Correct 35 ms 836 KB Output is correct

Subtask #10
10.0 / 10.0

# Verdict Execution time Memory Grader output
1 Correct 127 ms 924 KB Output is correct
2 Correct 129 ms 1008 KB Output is correct
3 Correct 137 ms 1096 KB Output is correct