Submission #1263297

#	Time	Username	Problem	Language	Result	Execution time	Memory
1263297		vidux	Trains (BOI24_trains)	C++17	0 / 100	34 ms	24388 KiB

Main

#include <bits/stdc++.h>
using namespace std;
#define SINGLE_TEST 1

typedef long long ll;
typedef unsigned long long ull; 
typedef long double ld;
typedef pair<int, int> pii;
typedef pair<ll, ll> pll;
typedef vector<int> vi;
typedef vector<vi> vvi;
typedef vector<ll> vl;
typedef vector<vl> vvl;

#define FOR(i, n) for (int(i) = 0; (i) < (n); ++(i))
#define REP(i, k, n) for (int(i) = (k); (i) <= (n); ++(i))
#define REPR(i, k, n) for (int(i) = (k); (i) >= (n); --(i))
#define FORR(x, arr) for (auto &x : arr)
#define FORR2(x, y, arr) for (auto &[x, y] : arr)
#define ALL(a) (a.begin()), (a.end())
#define RALL(a) (a.rbegin()), (a.rend())
#define REVERSE(v) reverse(ALL(v))
#define SZ(x) (int)(x).size()
#define fi first
#define se second
#define debug(x) cerr << #x << " = " << (x) << endl

const int MOD = 1e9 + 7;
const int INF = 1e9;
const ll LLINF = 1e18;

void solve() {
	int n; cin >> n;
	vl d(n), x(n);
	FOR(i, n) cin >> d[i] >> x[i];
	vector<unordered_map<int, ll>> v(n);
	vl ways(n);
	ways[0] = 1;
	ll ans = 0;
	FOR(i, n) {
		ans = (ans + ways[i]) % MOD;
		if (x[i] && d[i]) v[i][d[i]] = max(v[i][d[i]], d[i]*x[i]+i);
		FORR2(len, mx, v[i]) if (i+len < n && i+len <= mx) {
			ways[i+len] += ways[i];
			if (i+len < mx) v[i+len][len] = max(v[i+len][len], mx);
		}
	}
	cout << ans << endl;
}

int main() {
	ios_base::sync_with_stdio(false);
	cin.tie(NULL);

#if SINGLE_TEST
	solve();
#else
	int t;
	cin >> t;
	while (t--) {
		solve();
	}
#endif

	return 0;
}

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