Submission #1261903

#	Time	Username	Problem	Language	Result	Execution time	Memory
1261903		CrabCNH	Trains (BOI24_trains)	C++20	8 / 100	491 ms	1592 KiB

Main

#include <bits/stdc++.h>

#define task     "BriantheCrab"

#define int    long long
#define pii    pair <int, int>
#define fi     first
#define se     second
#define szf    sizeof
#define sz(s)  (int)((s).size())
#define all(v) (v).begin(), (v).end()

typedef long long ll;
typedef unsigned long long ull;
typedef long double ld;

using namespace std;

template <class T> void minimize (T &t, T f) {if (t > f) t = f;}
template <class T> void maximize (T &t, T f) {if (t < f) t = f;}

const int maxN = 2e5 + 5;
const int inf = 1e18 + 7;
const int mod = 1e9 + 7;

// khong tu code thi khong kha len duoc dau
// biet sol roi thi tu lam not di

int d[maxN], x[maxN];
int dp[maxN];

void solve () {
    int n;
    cin >> n;
    for (int i = 1; i <= n; i ++) {
        cin >> d[i] >> x[i];
    }
    dp[1] = 1;
    for (int i = 1; i <= n; i ++) {
        if (d[i] == 0) {
            continue;
        }
        for (int t = 1; t <= x[i]; t ++) {
            if (i + t * d[i] > n) {
                break;
            }
            (dp[i + t * d[i]] += dp[i]) %= mod;
        }
    }
    int res = 0;
    for (int i = 1; i <= n; i ++) {
        (res += dp[i]) % mod;
    }
    cout << res;
    return;
}

signed main () {
    cin.tie (nullptr) -> sync_with_stdio (false);
    if (fopen (task".inp", "r")) {
        freopen (task".inp", "r", stdin);
        freopen (task".out", "w", stdout);
    }
    int t = 1;
    //cin >> t;
    while (t --) {
        solve ();
    } 
    return 0;
}
// thfv

Compilation message (stderr)

Main.cpp: In function 'int main()':
Main.cpp:61:17: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   61 |         freopen (task".inp", "r", stdin);
      |         ~~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~
Main.cpp:62:17: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   62 |         freopen (task".out", "w", stdout);
      |         ~~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~

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