#include <bits/stdc++.h> //Andrei Alexandru a.k.a Sho10
#define ll long long
#define double long double
#pragma GCC optimize("O3")
#pragma GCC optimize("Ofast")
#define all(a) (a).begin(), (a).end()
#define f first
#define s second
#define pb push_back
#define mp make_pair
#define pi pair
#define rc(s) return cout<<s,0
#define endl '\n'
#define mod 1000007
#define PI 3.14159265359
#define MAXN 100005
#define INF 1000000005
#define LINF 1000000000000000005ll
#define CODE_START ios_base::sync_with_stdio(false);cin.tie(0);cout.tie(0);
using namespace std;
ll n,a[10005],pref[10005],dp[10005],dp2[10005];
int32_t main(){
CODE_START;
cin>>n;
for(ll i=1;i<=n;i++)
{
cin>>a[i];
pref[i]=max(pref[i-1],a[i]);
}
ll ans=1;
for(ll i=n;i>=1;i--)
{
if(i==n){
for(ll j=0;j<=n;j++)
{
dp[j]=1;
}
}else {
for(ll j=0;j<i;j++)
{
dp[j]=((j*dp2[j])%mod+dp2[j+1])%mod;
}
}
ans=(ans+((a[i]-1)*dp[pref[i-1]]%mod)%mod)%mod;
swap(dp,dp2);
}
cout<<ans<<endl;
}
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
1 ms |
492 KB |
Output is correct |
2 |
Correct |
1 ms |
492 KB |
Output is correct |
3 |
Correct |
1 ms |
492 KB |
Output is correct |
4 |
Correct |
1 ms |
492 KB |
Output is correct |
5 |
Correct |
1 ms |
492 KB |
Output is correct |
6 |
Correct |
1 ms |
492 KB |
Output is correct |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
1 ms |
492 KB |
Output is correct |
2 |
Correct |
1 ms |
492 KB |
Output is correct |
3 |
Correct |
1 ms |
492 KB |
Output is correct |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
1 ms |
492 KB |
Output is correct |
2 |
Correct |
1 ms |
492 KB |
Output is correct |
3 |
Correct |
1 ms |
492 KB |
Output is correct |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
2 ms |
492 KB |
Output is correct |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
1 ms |
492 KB |
Output is correct |
2 |
Correct |
1 ms |
492 KB |
Output is correct |
3 |
Correct |
2 ms |
512 KB |
Output is correct |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
4 ms |
492 KB |
Output is correct |
2 |
Correct |
4 ms |
492 KB |
Output is correct |
3 |
Correct |
4 ms |
492 KB |
Output is correct |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
9 ms |
492 KB |
Output is correct |
2 |
Correct |
9 ms |
492 KB |
Output is correct |
3 |
Correct |
10 ms |
492 KB |
Output is correct |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
241 ms |
748 KB |
Output is correct |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
77 ms |
748 KB |
Output is correct |
2 |
Correct |
76 ms |
620 KB |
Output is correct |
3 |
Correct |
77 ms |
620 KB |
Output is correct |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
244 ms |
748 KB |
Output is correct |
2 |
Correct |
264 ms |
748 KB |
Output is correct |
3 |
Correct |
250 ms |
748 KB |
Output is correct |