Submission #775845

#	Time	Username	Problem	Language	Result	Execution time	Memory
775845		SanguineChameleon	Radio Towers (IOI22_towers)	C++17	18 / 100	766 ms	1996 KiB

towers

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

const int maxN = 1e5 + 20;
bool sub1;
int cnt_min[maxN];
int H[maxN];
int N;
int max_id;

void init(int _N, vector<int> _H) {
	N = _N;
	for (int i = 0; i < N; i++) {
		H[i] = _H[i];
	}
	max_id = 0;
	for (int i = 0; i < N; i++) {
		if (H[i] > H[max_id]) {
			max_id = i;
		}
	}
	sub1 = true;
	for (int i = 0; i < max_id; i++) {
		sub1 &= H[i] < H[i + 1];
	}
	for (int i = max_id; i + 1 < N; i++) {
		sub1 &= H[i] > H[i + 1];
	}
	for (int i = 1; i < N - 1; i++) {
		cnt_min[i] = cnt_min[i - 1] + (H[i] < H[i - 1] && H[i] < H[i + 1]);
	}
}

int max_towers(int L, int R, int D) {
	if (L == R) {
		return 1;
	}
	if (sub1) {
		if (R <= max_id) {
			return 1;
		}
		else if (L >= max_id) {
			return 1;
		}
		else {
			return 1 + (H[max_id] >= max(H[L], H[R]) + D);
		}
	}
	if (D == 1) {
		return cnt_min[R - 1] - cnt_min[L] + (H[L] < H[L + 1]) + (H[R] < H[R - 1]);
	}
	return 0;
}

• Subtask 1: 4 / 4
• Subtask 2: 0 / 11
• Subtask 3: 0 / 12
• Subtask 4: 14 / 14
• Subtask 5: 0 / 17
• Subtask 6: 0 / 19
• Subtask 7: 0 / 23