Submission #1051607

#	Time	Username	Problem	Language	Result	Execution time	Memory
1051607		mindiyak	Trains (BOI24_trains)	C++14	21 / 100	2095 ms	2904 KiB

Main

#pragma GCC optimize("O1,O2,O3,Ofast,unroll-loops")
#include <bits/stdc++.h>
#include <string>
#include <iostream>
#include <cmath>
#include <numeric>
#include <stack>
#include <queue>
using namespace std;
typedef long long ll;
typedef unsigned long long ull;
typedef long double ld;
typedef pair<int, int> pi;
typedef pair<ll, ll> pl;
typedef pair<ld, ld> pd;
typedef vector<int> vi;
typedef vector<bool> vb;
typedef vector<vector<int>> vvi;
typedef vector<vector<pi>> vvpi;
typedef vector<ld> vd;
typedef vector<long long> vl;
typedef vector<pi> vpi;
typedef vector<pl> vpl;
#define FOR(i, a, b) for (ll i = a; i < (b); i++)
#define F0R(i, a) for (int i = 0; i < (a); i++)
#define FORd(i, a, b) for (int i = (b)-1; i >= a; i--)
#define F0Rd(i, a) for (int i = (a)-1; i >= 0; i--)
#define trav(a, x) for (auto &a : x)
#define uid(a, b) uniform_int_distribution<int>(a, b)(rng)
#define len(x) (int)(x).size()
#define mp make_pair
#define pb push_back
#define F first
#define nl endl
#define S second
#define lb lower_bound
#define ub upper_bound
#define aint(x) x.begin(), x.end()
#define raint(x) x.rbegin(), x.rend()
#define ins insert
const int M = 1e9+7;
void init(string name)
{
    freopen((name + ".in").c_str(), "r", stdin);
    freopen((name + ".out").c_str(), "w", stdout);
}
void fastIO()
{
    ios_base::sync_with_stdio(0);
    cin.tie(0);
}

int N;
ll ans = 0;
vi dp(1e5+10,0);

void solve()
{
    cin >> N;
    vpi arr(N);

    FOR(i,0,N){
        int d,t;cin >> d >> t;
        arr[i] = {d,t};
    }

    dp[1] = 1;

    // cout << endl;

    FOR(i,0,N){
        if(arr[i].F == 0)continue;
        for(int j = 1;j <= arr[i].S;j++){
            int cur = i+1+arr[i].F*j;
            // cout << i+1 << " " << cur << " " << dp[i+1] << endl;
            if(cur > N)break;
            dp[cur] += dp[i+1];
            dp[cur] %= M;
        }
    }

    // cout << endl;

    FOR(i,0,N+1){
        // cout << i << " " << dp[i] << endl;
        ans += dp[i];
        ans%=M;
    }

    cout << ans << endl;
}   


int main()
{
    fastIO();
    // init("test");
    int t = 1;
    // cin >> t;
    while (t--)
        solve();
    return 0;
}

Compilation message (stderr)

Main.cpp: In function 'void init(std::string)':
Main.cpp:44:12: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   44 |     freopen((name + ".in").c_str(), "r", stdin);
      |     ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Main.cpp:45:12: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   45 |     freopen((name + ".out").c_str(), "w", stdout);
      |     ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

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