Submission #1121756

#	Time	Username	Problem	Language	Result	Execution time	Memory
1121756		vjudge1	Calvinball championship (CEOI15_teams)	C++17	0 / 100	2 ms	848 KiB

teams

#include <bits/stdc++.h>
#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/tree_policy.hpp>
#define run  ios_base::sync_with_stdio(false);cin.tie(0);
 
#define ll long long
#define pll pair<ll, ll>
#define ull unsigned ll
#define ld double
#define endl "\n"
#define pb push_back
#define fi first
#define se second
 
#define pi acos(-1)
#define N 100007
#define minimum -9223372036854775807
#define maximum -minimum
#define mod 1000000007
 
using namespace std;
using namespace __gnu_pbds;
template <class t>
using ordered_set=tree<t, null_type,less_equal<t>, rb_tree_tag,tree_order_statistics_node_update>;

mt19937 rng(chrono::steady_clock::now().time_since_epoch().count());

ll gcd(ll a, ll b)
{
	if(b==0)
		return a;
	return gcd(b, a%b);
}

ll lcm(ll a, ll b)
{
	return a/gcd(a, b)*b;
}

bool isprime(ll n)
{
	if(n==1)
		return 0;
	for(ll i=2; i*i<=n; i++)
	{
		if(n%i==0)
			return 0;
	}
	return 1;
}

ll binpow(ll a, ll b)
{
    a%=mod;
    ll res=1;
    while(b>0)
	{
        if(b%2==1)
            res=(res*a)%mod;
        a=(a*a)%mod;
        b/=2;
    }
    return res;
}

ll dp[N];

const int modd=1000007;

int main()
{
	run;
	ll n;
	cin>>n;
	ll a[n+1];
	for(ll i=1; i<=n; i++)
	{
		cin>>a[i];
	}
	dp[1]=1;
	ll pref[n+1];
	pref[1]=1;
	for(ll i=2; i<=n; i++)
	{
		dp[i]=pref[i-1]+dp[i-1]%modd;
		pref[i]=pref[i-1]+dp[i];
		pref[i]%=modd;
	}
	cout<<dp[n]%modd<<endl;
}
/*

1 - 1
2 - 2
3 - 5
4 - 13
5 - 34

1
1  1

2
1 1  1
1 2  2

3 
1 1 1  1
1 1 2  2
1 2 1  3
1 2 2  4
1 2 3  5

4
1 1 1 1  1
1 1 1 2  2
1 1 2 1  3
1 1 2 2  4
1 1 2 3  5
1 2 1 1  6
1 2 1 2  7
1 2 2 1  8
1 2 2 2  9
1 2 2 3  10
1 2 3 2  11
1 2 3 3  12
1 2 3 4  13



5
1 1 1 1 1  1
1 1 1 1 2  2
1 1 1 2 1  3
1 1 1 2 2  4
1 1 1 2 3  5
1 1 2 1 1  6
1 1 2 1 2  7
1 1 2 2 1  8
1 1 2 2 2  9
1 1 2 2 3  10
1 1 2 3 2  11
1 1 2 3 3  12
1 1 2 3 4  13
1 2 1 1 1  14
1 2 1 1 2  15
1 2 1 2 1  16
1 2 1 2 2  17
1 2 1 2 3  18
1 2 2 1 1  19
1 2 2 1 2  20
1 2 2 2 1  21
1 2 2 2 2  22
1 2 2 2 3  23
1 2 2 3 2  24
1 2 2 3 3  25
1 2 2 3 4  26
1 2 3 2 1  27
1 2 3 2 2  28
1 2 3 2 3  29
1 2 3 3 2  30
1 2 3 3 3  31
1 2 3 3 4  32
1 2 3 4 4  33
1 2 3 4 5  34
*/
// By Xanlar

• Subtask 1: 0 / 10
• Subtask 2: 0 / 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