Submission #1059338

#	Time	Username	Problem	Language	Result	Execution time	Memory
1059338		ten_xd	Trains (BOI24_trains)	C++17	100 / 100	231 ms	126992 KiB

Main

#include<bits/stdc++.h>
using namespace std;
typedef long long ll;
typedef unsigned long long ull;
typedef long double ld;
#define rep(a,b) for(int a = 0; a < (b); ++a)
#define all(t) t.begin(), t.end()
#define pb push_back

const int N = 1e5+5, INF = 2e9+54321, mod = 1e9+7, K = 317;
const ll INF_L = (ll)2e18+54321;

int n, wyn;
int D[N], X[N], dp[N], S[K][N];

void solve()
{
	cin >> n;
	rep(i,n) cin >> D[i] >> X[i];

	wyn = 0, dp[0] = 1;
	rep(i,n)
	{
		for(int j = 1; j < K; ++j) if(i-j >= 0) S[j][i] = (S[j][i]+S[j][i-j]) % mod;

		for(int j = 1; j < K; ++j) dp[i] = (dp[i]+S[j][i]) % mod;
		wyn = (wyn+dp[i]) % mod;

		if(D[i] >= K)
		{
			for(int j = 1; j <= X[i] and (ll)i+(ll)j*D[i] < (ll)n; ++j)
			{
				dp[i+j*D[i]] = (dp[i+j*D[i]]+dp[i]) % mod;
			}
		}
		else
		{
			S[D[i]][i] = (S[D[i]][i]+dp[i]) % mod;
			S[D[i]][min((ll)n,(ll)i+(ll)(X[i]+1)*D[i])] = (S[D[i]][min((ll)n,(ll)i+(ll)(X[i]+1)*D[i])]-dp[i]+mod) % mod;
		}

		/*cout << '\n' << '\n';
		cout << "I: " << i << " DP: " << dp[i] << '\n';
		for(int j = 0; j <= 10; ++j) cout << "J: " << j << " S: " << S[j][i] << '\n';
		cout << '\n' << '\n';*/
	}

	cout << wyn << '\n';
}

int main()
{   
    ios_base::sync_with_stdio(0);
    cin.tie(0);

    int T = 1;
   	//cin >> T;
    while(T--) solve();

    return 0;
}

• Subtask 1: 8 / 8
• Subtask 2: 13 / 13
• Subtask 3: 16 / 16
• Subtask 4: 34 / 34
• Subtask 5: 29 / 29