Submission #1255599

#	Time	Username	Problem	Language	Result	Execution time	Memory
1255599		Zbyszek99	Trains (BOI24_trains)	C++20	100 / 100	180 ms	7700 KiB

Main

#include <bits/stdc++.h>
#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/tree_policy.hpp>
#define ll long long
#define ld long double
#define ull unsigned long long
#define ff first
#define ss second
#define pii pair<int,int>
#define pll pair<long long, long long>
#define vi vector<int>
#define vl vector<long long>
#define pb push_back
#define rep(i, b) for(int i = 0; i < (b); ++i)
#define rep2(i,a,b) for(int i = a; i <= (b); ++i)
#define rep3(i,a,b,c) for(int i = a; i <= (b); i+=c)
#define count_bits(x) __builtin_popcountll((x))
#define all(x) (x).begin(),(x).end()
#define siz(x) (int)(x).size()
#define forall(it,x) for(auto& it:(x))
using namespace __gnu_pbds;
using namespace std;
typedef tree<int, null_type, less<int>, rb_tree_tag,tree_order_statistics_node_update> ordered_set;
//mt19937 mt;void random_start(){mt.seed(chrono::time_point_cast<chrono::milliseconds>(chrono::high_resolution_clock::now()).time_since_epoch().count());}
//ll los(ll a, ll b) {return a + (mt() % (b-a+1));}
const int INF = 1e9+50;
const ll INF_L = 1e18+40;
const ll MOD = 1e9+7;

const int sqr = 400;

ll dp[100001];
ll D[100001];
ll X[100001];
ll dp_mod[sqr+1][sqr+1];
vi del[100001];

int main()
{
    ios_base::sync_with_stdio(0);cin.tie(0);cout.tie(0);
    //random_start();
    int n;
    cin >> n;
    rep2(i,1,n) cin >> D[i] >> X[i];
    dp[1] = 1;
    ll ans = 0;
    rep2(i,1,n)
    {
        forall(it,del[i])
        {
            dp_mod[D[it]][it%D[it]] = (dp_mod[D[it]][it%D[it]]-dp[it]+MOD)%MOD; 
        }
        rep2(j,1,sqr)
        {
            dp[i] = (dp[i]+dp_mod[j][i%j])%MOD;
        }
        ans += dp[i];
        ans %= MOD;
        if(D[i] == 0) continue;
        if(D[i] > sqr)
        {
            rep2(j,1,X[i])
            {
                ll poz = i+D[i]*j;
                if(poz > n) break;
                dp[poz] = (dp[poz]+dp[i])%MOD;
            }
        }
        else
        {
            dp_mod[D[i]][i%D[i]] = (dp_mod[D[i]][i%D[i]]+dp[i])%MOD;
            ll poz = i+D[i]*(X[i]+1);
            if(poz <= n) del[poz].pb(i);
        }
    }
    cout << ans << "\n";
}

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