Submission #1033741

#	Time	Username	Problem	Language	Result	Execution time	Memory
1033741		Tozzyyyy	Trains (BOI24_trains)	C++14	42 / 100	149 ms	9164 KiB

Main

#ifdef LOCAL
#include "D:\debug.h"
#else
#define cebug(...) "anHiepORZ"
#endif

#pragma GCC optimize("Ofast,unroll-loops")
#pragma GCC target("avx2,bmi,bmi2,lzcnt,popcnt")

#include <bits/stdc++.h>
using namespace std;

#include <ext/pb_ds/assoc_container.hpp> 
#include <ext/pb_ds/tree_policy.hpp> 
using namespace __gnu_pbds; 
  
#define ordered_set tree<int, null_type,less_equal<int>, rb_tree_tag,tree_order_statistics_node_update> 

//less: set
//less_equal: multiset (ko dung dc ham ...)

#define fi first
#define se second
#define pb push_back

//COUNTDOWN: 9 days left
//COUNTDOWN: 9 days left
//COUNTDOWN: 9 days left
//COUNTDOWN: 9 days left
//COUNTDOWN: 9 days left
//COUNTDOWN: 9 days left
//COUNTDOWN: 9 days left
//COUNTDOWN: 9 days left


#define int long long

const int N =  1e5 + 10;
const int mod = 1e9 + 7;
const int oo = 1e18;

int n;
pair<int,int> a[N];
int dp[N];
const int S = 316;
int rem[S + 10][S + 10];
vector<pair<pair<int,int>, int>> del[N];

void solve(){
    cin >> n;
    for(int i = 1; i <= n; i++){
        cin >> a[i].first >> a[i].second;
    }
    // dp[1] = 1;
    // int ans = 1;
    // for(int i = 2; i <= n; i++){
    //     for(int j = 1; j < i; j++){
    //         if(a[j].first == 0 || (i - j) % a[j].first) continue;
    //         if(i > j + a[j].second * a[j].first) continue;
    //         dp[i] = (dp[i] + dp[j])%mod;
    //     }
    //     ans = (ans + dp[i])%mod;
    // }
    // cout << ans;
    dp[1] = 1;
    for(int i = 1; i <= n; i++){
        // cebug(i);
        //del:
        for(auto &x : del[i]){
            rem[x.first.first][x.first.second] = (rem[x.first.first][x.first.second] - x.second)%mod;
        }
        // cebug(1);
        //add:
        for(int j = 1; j < S; j++){
            dp[i] = (dp[i] + rem[j][i % j])%mod;
        }
        // cebug(2);
        // cebug(a[i]);
        //pr:
        if(a[i].first == 0) continue;
        if(a[i].first >= S){
            int x = 1;
            for(int j = i + a[i].first; j <= n; j += a[i].first){
                if(x > a[i].second) break;
                x++;
                dp[j] = (dp[j] + dp[i])%mod;
            }
        }
        else{
            rem[a[i].first][i % a[i].first] = (rem[a[i].first][i % a[i].first] +  dp[i]) %mod;
            del[min(n + 1, i + a[i].first * a[i].second + 1)].push_back(make_pair(make_pair(a[i].first, i % a[i].first), dp[i] % mod));
        }
    }
    int sum = 0;
    for(int i = 1; i <= n; i++) sum = (sum + dp[i]) % mod;
    cout << sum;
}

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

    int tc; tc = 1;
    while(tc--)
        solve();
    return 0;
}

• Subtask 1: 8 / 8
• Subtask 2: 0 / 13
• Subtask 3: 0 / 16
• Subtask 4: 34 / 34
• Subtask 5: 0 / 29