Submission #1086030

#	Time	Username	Problem	Language	Result	Execution time	Memory
1086030		Mr_Ph	Trains (BOI24_trains)	C++17	100 / 100	160 ms	7872 KiB

Main

#include<bits/stdc++.h>
using namespace std;
const int mod=(int)1e9+7; 
#define endl '\n'
#define all(arr) arr.begin(),arr.end()
#define allr(arr) arr.rbegin(),arr.rend()
#define sz size()
#define int long long
int dp[100002];
void iforgor()
{
    int n;
    cin>>n;
    dp[0]=1;
    int pog=sqrt(n);
    vector<vector<int>>dp1(pog,vector<int>(pog));
    // cout<<pog<<endl;
    vector<vector<array<int,3>>>nig(n);
    for(int i=0;i<n;i++)
    {
        int d,x;
        cin>>d>>x;
        for(int j=1;j<pog;j++){
            int lo=i%j;
            dp[i]+=dp1[j][lo];
            dp[i]%=mod;
        }
        for(auto j:nig[i])
        {
            int lo=j[2],dd=j[1],dp1m=j[0];
            dp1[dd][lo]=(dp1[dd][lo]-dp1m+mod)%mod;
        }
        if(x==0||d==0)continue;
        if(d>=pog){
            for(int j=i+d;j<n;j+=d)
            {
                x--;
                if(x<0)break;
                dp[j]+=dp[i];
                dp[j]%=mod;
            }
        }
        else
        {
            int lo=i%d;
            dp1[d][lo]+=dp[i];
            dp1[d][lo]%=mod;
            if((i+d*x)<n)nig[i+d*x].push_back({dp[i],d,lo});
        }
    }
    int ans=0;
    for(int i=0;i<n;i++)ans+=dp[i],ans%=mod;
    cout<<ans<<endl;
}   
signed main()
{
    ios_base::sync_with_stdio(false);   
    cin.tie(NULL);   
    int t=1;
    // cin>>t;
    while(t--)iforgor();
}   

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