답안 #96988 :: oj.uz

#	제출 시각	아이디	문제	언어	결과	실행 시간	메모리
96988	2019-02-13T07:54:59 Z	diamond_duke	Sparklers (JOI17_sparklers)	C++11	100 / 100	366 ms	17016 KB

sparklers

#include <algorithm>
#include <cstdio>
using ll = long long;
struct ST_table
{
	using func_T = int (*)(int, int);
	int n, lg[100005], arr[25][100005];
	func_T comp;
	ST_table(int _n, func_T _comp) : n(_n), comp(_comp)
	{
		lg[0] = lg[1] = 0;
		for (int i = 2; i <= n; i++)
			lg[i] = lg[i >> 1] + 1;
		for (int i = 0; i < n; i++)
			arr[0][i] = i;
		for (int i = 1; i <= lg[n]; i++)
		{
			for (int j = 0; j + (1 << i) <= n; j++)
				arr[i][j] = comp(arr[i - 1][j], arr[i - 1][j + (1 << i - 1)]);
		}
	}
	inline int operator ()(int l, int r)
	{
		int len = lg[r - l + 1];
		return comp(arr[len][l], arr[len][r - (1 << len) + 1]);
	}
};
int pos[100005], stk[100005], pre[100005], nxt[100005];
ll arr[100005];
inline int smaller(int x, int y) { return arr[x] < arr[y] ? x : y; }
inline int larger(int x, int y) { return arr[x] > arr[y] ? x : y; }
inline bool check(int n, int st, ll T)
{
	for (int i = 0; i < n; i++)
		arr[i] = pos[i] - T * i;
	ST_table query_min(n, smaller), query_max(n, larger);
	auto find_bigger = [&] (int *res)
	{
		int tp = 0;
		stk[tp] = -1;
		for (int i = 0; i < n; i++)
		{
			while (tp && arr[stk[tp]] <= arr[i])
				tp--;
			res[i] = stk[tp];
			stk[++tp] = i;
		}
		std::reverse(arr, arr + n);
		for (int i = 0; i < n; i++)
			arr[i] *= -1;
	};
	find_bigger(pre);
	find_bigger(nxt);
	std::reverse(nxt, nxt + n);
	for (int i = 0; i < n; i++)
		nxt[i] = n - nxt[i] - 1;
	int l = st, r = st;
	while (l || r != n - 1)
	{
		auto try_l = [&] (int x)
		{
			if (x < 0 || arr[query_min(x, l - 1)] < arr[r])
				return false;
			l = x;
			return true;
		};
		auto try_r = [&] (int y)
		{
			if (y >= n || arr[query_max(r + 1, y)] > arr[l])
				return false;
			r = y;
			return true;
		};
		if (try_l(pre[l]) || try_r(nxt[r]))
			continue;
		if (!l)
			return arr[query_max(r + 1, n - 1)] <= arr[l];
		if (r == n - 1)
			return arr[query_min(0, l - 1)] >= arr[r];
		int x = query_min(0, l - 1), y = query_max(r + 1, n - 1);
		if (arr[x] < arr[r] || arr[y] > arr[l])
			return false;
		int a = query_max(0, x), b = query_min(y, n - 1);
		if (arr[a] >= arr[y])
			l = a;
		else if (arr[b] <= arr[x])
			r = b;
		else
			return false;
	}
	return true;
}
int main()
{
	// freopen("JOISC2017-D1T3.in", "r", stdin);
	int n, st, T;
	scanf("%d%d%d", &n, &st, &T);
	for (int i = 0; i < n; i++)
		scanf("%d", pos + i);
	int l = 0, r = 1e9, res = -1;
	while (l <= r)
	{
		int m = l + r >> 1;
		if (check(n, st - 1, (ll)m * T * 2))
		{
			res = m;
			r = m - 1;
		}
		else
			l = m + 1;
	}
	printf("%d\n", res);
	return 0;
}

Compilation message

sparklers.cpp: In constructor 'ST_table::ST_table(int, ST_table::func_T)':
sparklers.cpp:19:60: warning: suggest parentheses around '-' inside '<<' [-Wparentheses]
     arr[i][j] = comp(arr[i - 1][j], arr[i - 1][j + (1 << i - 1)]);
                                                          ~~^~~
sparklers.cpp: In function 'int main()':
sparklers.cpp:103:13: warning: suggest parentheses around '+' inside '>>' [-Wparentheses]
   int m = l + r >> 1;
           ~~^~~
sparklers.cpp:97:7: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
  scanf("%d%d%d", &n, &st, &T);
  ~~~~~^~~~~~~~~~~~~~~~~~~~~~~
sparklers.cpp:99:8: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   scanf("%d", pos + i);
   ~~~~~^~~~~~~~~~~~~~~

Subtask #1
30.0 / 30.0

#	결과	실행 시간	메모리	Grader output
1	Correct	2 ms	384 KB	Output is correct
2	Correct	2 ms	384 KB	Output is correct
3	Correct	2 ms	384 KB	Output is correct
4	Correct	4 ms	384 KB	Output is correct
5	Correct	2 ms	384 KB	Output is correct
6	Correct	3 ms	384 KB	Output is correct
7	Correct	3 ms	384 KB	Output is correct
8	Correct	3 ms	384 KB	Output is correct
9	Correct	3 ms	384 KB	Output is correct
10	Correct	2 ms	384 KB	Output is correct
11	Correct	2 ms	384 KB	Output is correct
12	Correct	3 ms	384 KB	Output is correct
13	Correct	3 ms	384 KB	Output is correct
14	Correct	3 ms	384 KB	Output is correct
15	Correct	3 ms	384 KB	Output is correct
16	Correct	3 ms	384 KB	Output is correct
17	Correct	2 ms	384 KB	Output is correct
18	Correct	2 ms	384 KB	Output is correct
19	Correct	3 ms	384 KB	Output is correct
20	Correct	3 ms	384 KB	Output is correct
21	Correct	3 ms	384 KB	Output is correct

Subtask #2
20.0 / 20.0

#	결과	실행 시간	메모리	Grader output
1	Correct	2 ms	384 KB	Output is correct
2	Correct	2 ms	384 KB	Output is correct
3	Correct	2 ms	384 KB	Output is correct
4	Correct	4 ms	384 KB	Output is correct
5	Correct	2 ms	384 KB	Output is correct
6	Correct	3 ms	384 KB	Output is correct
7	Correct	3 ms	384 KB	Output is correct
8	Correct	3 ms	384 KB	Output is correct
9	Correct	3 ms	384 KB	Output is correct
10	Correct	2 ms	384 KB	Output is correct
11	Correct	2 ms	384 KB	Output is correct
12	Correct	3 ms	384 KB	Output is correct
13	Correct	3 ms	384 KB	Output is correct
14	Correct	3 ms	384 KB	Output is correct
15	Correct	3 ms	384 KB	Output is correct
16	Correct	3 ms	384 KB	Output is correct
17	Correct	2 ms	384 KB	Output is correct
18	Correct	2 ms	384 KB	Output is correct
19	Correct	3 ms	384 KB	Output is correct
20	Correct	3 ms	384 KB	Output is correct
21	Correct	3 ms	384 KB	Output is correct
22	Correct	6 ms	512 KB	Output is correct
23	Correct	3 ms	512 KB	Output is correct
24	Correct	4 ms	512 KB	Output is correct
25	Correct	6 ms	512 KB	Output is correct
26	Correct	5 ms	512 KB	Output is correct
27	Correct	6 ms	512 KB	Output is correct
28	Correct	5 ms	512 KB	Output is correct
29	Correct	6 ms	512 KB	Output is correct
30	Correct	6 ms	512 KB	Output is correct
31	Correct	5 ms	640 KB	Output is correct
32	Correct	4 ms	512 KB	Output is correct
33	Correct	5 ms	640 KB	Output is correct
34	Correct	5 ms	640 KB	Output is correct
35	Correct	5 ms	512 KB	Output is correct
36	Correct	6 ms	512 KB	Output is correct
37	Correct	4 ms	512 KB	Output is correct
38	Correct	4 ms	512 KB	Output is correct
39	Correct	5 ms	512 KB	Output is correct
40	Correct	4 ms	512 KB	Output is correct

Subtask #3
50.0 / 50.0

#	결과	실행 시간	메모리	Grader output
1	Correct	2 ms	384 KB	Output is correct
2	Correct	2 ms	384 KB	Output is correct
3	Correct	2 ms	384 KB	Output is correct
4	Correct	4 ms	384 KB	Output is correct
5	Correct	2 ms	384 KB	Output is correct
6	Correct	3 ms	384 KB	Output is correct
7	Correct	3 ms	384 KB	Output is correct
8	Correct	3 ms	384 KB	Output is correct
9	Correct	3 ms	384 KB	Output is correct
10	Correct	2 ms	384 KB	Output is correct
11	Correct	2 ms	384 KB	Output is correct
12	Correct	3 ms	384 KB	Output is correct
13	Correct	3 ms	384 KB	Output is correct
14	Correct	3 ms	384 KB	Output is correct
15	Correct	3 ms	384 KB	Output is correct
16	Correct	3 ms	384 KB	Output is correct
17	Correct	2 ms	384 KB	Output is correct
18	Correct	2 ms	384 KB	Output is correct
19	Correct	3 ms	384 KB	Output is correct
20	Correct	3 ms	384 KB	Output is correct
21	Correct	3 ms	384 KB	Output is correct
22	Correct	6 ms	512 KB	Output is correct
23	Correct	3 ms	512 KB	Output is correct
24	Correct	4 ms	512 KB	Output is correct
25	Correct	6 ms	512 KB	Output is correct
26	Correct	5 ms	512 KB	Output is correct
27	Correct	6 ms	512 KB	Output is correct
28	Correct	5 ms	512 KB	Output is correct
29	Correct	6 ms	512 KB	Output is correct
30	Correct	6 ms	512 KB	Output is correct
31	Correct	5 ms	640 KB	Output is correct
32	Correct	4 ms	512 KB	Output is correct
33	Correct	5 ms	640 KB	Output is correct
34	Correct	5 ms	640 KB	Output is correct
35	Correct	5 ms	512 KB	Output is correct
36	Correct	6 ms	512 KB	Output is correct
37	Correct	4 ms	512 KB	Output is correct
38	Correct	4 ms	512 KB	Output is correct
39	Correct	5 ms	512 KB	Output is correct
40	Correct	4 ms	512 KB	Output is correct
41	Correct	193 ms	11052 KB	Output is correct
42	Correct	9 ms	888 KB	Output is correct
43	Correct	46 ms	3188 KB	Output is correct
44	Correct	310 ms	16824 KB	Output is correct
45	Correct	330 ms	16836 KB	Output is correct
46	Correct	327 ms	16800 KB	Output is correct
47	Correct	360 ms	16888 KB	Output is correct
48	Correct	287 ms	16760 KB	Output is correct
49	Correct	335 ms	16860 KB	Output is correct
50	Correct	348 ms	16888 KB	Output is correct
51	Correct	306 ms	17016 KB	Output is correct
52	Correct	328 ms	16764 KB	Output is correct
53	Correct	349 ms	16888 KB	Output is correct
54	Correct	358 ms	16888 KB	Output is correct
55	Correct	339 ms	16888 KB	Output is correct
56	Correct	343 ms	16760 KB	Output is correct
57	Correct	306 ms	16872 KB	Output is correct
58	Correct	277 ms	16808 KB	Output is correct
59	Correct	262 ms	16120 KB	Output is correct
60	Correct	292 ms	16888 KB	Output is correct
61	Correct	301 ms	16760 KB	Output is correct
62	Correct	366 ms	16760 KB	Output is correct
63	Correct	316 ms	16888 KB	Output is correct
64	Correct	330 ms	16888 KB	Output is correct
65	Correct	294 ms	16840 KB	Output is correct
66	Correct	302 ms	16760 KB	Output is correct
67	Correct	281 ms	16888 KB	Output is correct
68	Correct	322 ms	16888 KB	Output is correct
69	Correct	294 ms	16888 KB	Output is correct

답안 #96988

Compilation message

Subtask #1 30.0 / 30.0

Subtask #2 20.0 / 20.0

Subtask #3 50.0 / 50.0

Subtask #1
30.0 / 30.0

Subtask #2
20.0 / 20.0

Subtask #3
50.0 / 50.0