제출 #1137169

#	제출 시각	아이디	문제	언어	결과	실행 시간	메모리
1137169		SulA	Trains (BOI24_trains)	C++20	100 / 100	339 ms	250136 KiB

Main

#include <bits/stdc++.h>
#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/tree_policy.hpp>
#define bitcount __builtin_popcountll
#define all(a) (a).begin(), (a).end()
using namespace std;
using namespace __gnu_pbds;
template<typename T> using ordered_multiset = tree<T, null_type, less_equal<T>, rb_tree_tag, tree_order_statistics_node_update>;
#define int long long
const int MOD = 1e9+7;

signed main() {
    ios::sync_with_stdio(false);
    cin.tie(nullptr); cout.tie(nullptr);

    int n; cin>>n;
    int SQRT = 0;
    while ((SQRT + 1)*(SQRT + 1) < n) SQRT++;
    int jump[n], lim[n];
    for (int i = 0; i < n; cin>> jump[i] >> lim[i++]);
    // for (int i = 0; i < n; i++) {
    //     jump[i] = rand() % n;
    //     lim[i] = rand() % n + 1;
    //     cout<<jump[i]<<' '<<lim[i]<<'\n';
    // }
    int dp[n]{}, suff[SQRT][n];
    for (int i = n-1; i >= 0; i--) {
        if (jump[i] < SQRT) {
            long long d = jump[i], x = lim[i];
            dp[i] = i + d < n ? suff[d][i + d] : 0;
            if (i + d*(x+1) < n) dp[i] -= suff[d][i + d*(x+1)];
            if (dp[i] < 0) dp[i] += MOD;
        } else {
            for (int j = 1; j <= lim[i] && i + jump[i]*j < n; j++) {
                dp[i] += dp[i + j*jump[i]];
                if (dp[i] >= MOD) dp[i] -= MOD;
            }
        }
        dp[i] = (dp[i] + 1) % MOD;
        for (int j = 1; j < SQRT; j++) {
            suff[j][i] = dp[i];
            if (i + j < n) suff[j][i] += suff[j][i + j];
            if (suff[j][i] >= MOD) suff[j][i] -= MOD;
        }
    }
//    for (auto x : dp) cout<<x<<' ';
    cout<<dp[0];
}

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