Submission #135765

#	Time	Username	Problem	Language	Result	Execution time	Memory
135765		imyujin	MP3 Player (CEOI10_mp3player)	C++14	60 / 100	147 ms	6652 KiB

mp3player

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

typedef pair<int, int> pii;

#define fi first
#define se second

const int MAXN = 100005;

char B[MAXN];
int T[MAXN];
pii seg[4 * MAXN];
int lazy[4 * MAXN];
int ts[MAXN];

void updseg(int idx, int l, int r, int x, int y, int z) {
	if(x <= l && r <= y) {
		seg[idx].fi += z;
		seg[idx].se += z;
		lazy[idx] += z;
	}
	else if(l <= y && x <= r) {
		int m = (l + r) / 2;
		updseg(idx * 2, l, m, x, y, z);
		updseg(idx * 2 + 1, m + 1, r, x, y, z);
		seg[idx].fi = max(seg[idx * 2].fi, seg[idx * 2 + 1].fi) + lazy[idx];
		seg[idx].se = min(seg[idx * 2].se, seg[idx * 2 + 1].se) + lazy[idx];
	}
}

int main() {
	int N, Vm, V2;
	int ansT, ansV;

	cin >> N >> Vm >> V2;
	for(int i = 0; i < N; i++) cin >> B[i] >> T[i];

	for(int i = N - 1; i > 0; i--) T[i] -= T[i - 1];
	for(int i = 0; i < N - 1; i++) ts[i] = i + 1;
	sort(ts, ts + N - 1, [&](const int a, const int b) { return T[a] < T[b]; } );
	//for(int i = 0; i < N - 1; i++) printf("%d ", ts[i]);
	//printf("\n");

	ansT = T[ts[0]] - 1;
	ansV = V2;
	int sum = V2;
	for(int i = 1; i < 4 * N; i++) seg[i] = make_pair(V2, V2);
	for(int i = 0; i < N - 1; i++) {
		updseg(1, 0, N - 1, 0, ts[i], B[ts[i]] == '+' ? -1 : 1);
		sum += B[ts[i]] == '+' ? -1 : 1;
		if((i == N - 2 || T[ts[i]] != T[ts[i + 1]]) && seg[1].fi <= Vm && seg[1].se >= 0) {
			ansT = i == N - 2 ? -1 : (T[ts[i + 1]] - 1);
			ansV = seg[1].fi == Vm ? Vm : sum;
		}
		//printf("sum = %d, seg[1] = (%d, %d), ansT = %d, ansV = %d\n", sum, seg[1].fi, seg[1].se, ansT, ansV);
	}

	if(ansT == -1) cout << "infinity";
	else cout << ansT << " " << ansV;
	return 0;
}

• Subtask 1: 10 / 10
• Subtask 2: 10 / 10
• Subtask 3: 10 / 10
• Subtask 4: 10 / 10
• Subtask 5: 0 / 10
• Subtask 6: 0 / 10
• Subtask 7: 0 / 10
• Subtask 8: 0 / 10
• Subtask 9: 10 / 10
• Subtask 10: 10 / 10