Submission #745324

#	Submission time	Handle	Problem	Language	Result	Execution time	Memory
745324	2023-05-19T21:12:38 Z	rainboy	Exam (eJOI20_exam)	C	77 / 100	113 ms	98244 KB

exam

#include <stdio.h>

#define N	100000
#define N_	5000

int max(int a, int b) { return a > b ? a : b; }

unsigned int X = 12345;

int rand_() {
	return (X *= 3) >> 1;
}

void sort(int *ii, int l, int r) {
	while (l < r) {
		int i = l, j = l, k = r, i_ = ii[l + rand_() % (r - l)], tmp;

		while (j < k)
			if (ii[j] == i_)
				j++;
			else if (ii[j] < i_) {
				tmp = ii[i], ii[i] = ii[j], ii[j] = tmp;
				i++, j++;
			} else {
				k--;
				tmp = ii[j], ii[j] = ii[k], ii[k] = tmp;
			}
		sort(ii, l, i);
		l = k;
	}
}

int ft[N];

void update(int i, int n, int x) {
	while (i < n) {
		ft[i] = max(ft[i], x);
		i |= i + 1;
	}
}

int query(int i) {
	int x = 0;

	while (i >= 0) {
		x = max(x, ft[i]);
		i &= i + 1, i--;
	}
	return x;
}

int main() {
	static int aa[N], bb[N], qu[N], pp[N], qq[N], ii[N], dp[N_][N_];
	int n, cnt, i, j, b, k, lower, upper, same, good;

	scanf("%d", &n);
	for (i = 0; i < n; i++)
		scanf("%d", &aa[i]);
	for (i = 0; i < n; i++)
		scanf("%d", &bb[i]);
	same = 1;
	for (i = 1; i < n; i++)
		if (bb[i] != bb[i - 1]) {
			same = 0;
			break;
		}
	if (same) {
		b = bb[0], k = 0;
		for (i = 0; i < n; i++)
			if (aa[i] <= b) {
				j = i;
				good = 0;
				while (j < n && aa[j] <= b)
					if (aa[j++] == b)
						good = 1;
				if (good)
					k += j - i;
				i = j;
			}
		printf("%d\n", k);
		return 0;
	}
	cnt = 0;
	for (i = 0; i < n; i++) {
		while (cnt && aa[qu[cnt - 1]] <= aa[i])
			cnt--;
		pp[i] = cnt ? qu[cnt - 1] : -1;
		qu[cnt++] = i;
	}
	cnt = 0;
	for (i = n - 1; i >= 0; i--) {
		while (cnt && aa[qu[cnt - 1]] <= aa[i])
			cnt--;
		qq[i] = cnt ? qu[cnt - 1] : n;
		qu[cnt++] = i;
	}
	if (n <= N_) {
		for (i = 0; i < n; i++)
			for (j = 0; j < n; j++)
				dp[i][j] = max(i == 0 ? 0 : dp[i - 1][j], (j == 0 ? 0 : dp[i][j - 1]) + (aa[i] == bb[j] && pp[i] < j && j < qq[i] ? 1 : 0));
		printf("%d\n", dp[n - 1][n - 1]);
	} else {
		for (i = 0; i < n; i++)
			ii[i] = i;
		sort(ii, 0, n);
		for (j = 0; j < n; j++) {
			lower = -1, upper = n;
			while (upper - lower > 1) {
				i = (lower + upper) / 2;
				if (aa[ii[i]] <= bb[j])
					lower = i;
				else
					upper = i;
			}
			if (lower >= 0 && aa[i = ii[lower]] == bb[j] && pp[i] < j && j < qq[i])
				update(i, n, query(i) + 1);
		}
		printf("%d\n", query(n - 1));
	}
	return 0;
}

Compilation message

exam.c: In function 'main':
exam.c:56:2: warning: ignoring return value of 'scanf' declared with attribute 'warn_unused_result' [-Wunused-result]
   56 |  scanf("%d", &n);
      |  ^~~~~~~~~~~~~~~
exam.c:58:3: warning: ignoring return value of 'scanf' declared with attribute 'warn_unused_result' [-Wunused-result]
   58 |   scanf("%d", &aa[i]);
      |   ^~~~~~~~~~~~~~~~~~~
exam.c:60:3: warning: ignoring return value of 'scanf' declared with attribute 'warn_unused_result' [-Wunused-result]
   60 |   scanf("%d", &bb[i]);
      |   ^~~~~~~~~~~~~~~~~~~

Subtask #1

14.0 / 14.0

#	Verdict	Execution time	Memory	Grader output
1	Correct	0 ms	212 KB	Output is correct
2	Correct	0 ms	212 KB	Output is correct
3	Correct	0 ms	340 KB	Output is correct
4	Correct	1 ms	340 KB	Output is correct
5	Correct	0 ms	340 KB	Output is correct
6	Correct	0 ms	340 KB	Output is correct

Subtask #2

12.0 / 12.0

#	Verdict	Execution time	Memory	Grader output
1	Correct	1 ms	212 KB	Output is correct
2	Correct	5 ms	340 KB	Output is correct
3	Correct	17 ms	980 KB	Output is correct
4	Correct	16 ms	980 KB	Output is correct
5	Correct	25 ms	980 KB	Output is correct
6	Correct	16 ms	1064 KB	Output is correct
7	Correct	19 ms	952 KB	Output is correct
8	Correct	24 ms	956 KB	Output is correct

Subtask #3

13.0 / 13.0

#	Verdict	Execution time	Memory	Grader output
1	Correct	0 ms	340 KB	Output is correct
2	Correct	2 ms	3284 KB	Output is correct
3	Correct	16 ms	23892 KB	Output is correct
4	Correct	62 ms	94320 KB	Output is correct
5	Correct	67 ms	98244 KB	Output is correct
6	Correct	65 ms	98232 KB	Output is correct

Subtask #4

0 / 23.0

#	Verdict	Execution time	Memory	Grader output
1	Incorrect	2 ms	340 KB	Output isn't correct
2	Halted	0 ms	0 KB	-

Subtask #5

16.0 / 16.0

#	Verdict	Execution time	Memory	Grader output
1	Correct	0 ms	212 KB	Output is correct
2	Correct	0 ms	212 KB	Output is correct
3	Correct	0 ms	340 KB	Output is correct
4	Correct	1 ms	340 KB	Output is correct
5	Correct	0 ms	340 KB	Output is correct
6	Correct	0 ms	340 KB	Output is correct
7	Correct	0 ms	340 KB	Output is correct
8	Correct	0 ms	468 KB	Output is correct
9	Correct	1 ms	724 KB	Output is correct
10	Correct	1 ms	1236 KB	Output is correct
11	Correct	1 ms	1236 KB	Output is correct
12	Correct	1 ms	1236 KB	Output is correct
13	Correct	1 ms	1236 KB	Output is correct
14	Correct	1 ms	1236 KB	Output is correct

Subtask #6

22.0 / 22.0

#	Verdict	Execution time	Memory	Grader output
1	Correct	0 ms	212 KB	Output is correct
2	Correct	0 ms	212 KB	Output is correct
3	Correct	0 ms	340 KB	Output is correct
4	Correct	1 ms	340 KB	Output is correct
5	Correct	0 ms	340 KB	Output is correct
6	Correct	0 ms	340 KB	Output is correct
7	Correct	0 ms	340 KB	Output is correct
8	Correct	2 ms	3284 KB	Output is correct
9	Correct	16 ms	23892 KB	Output is correct
10	Correct	62 ms	94320 KB	Output is correct
11	Correct	67 ms	98244 KB	Output is correct
12	Correct	65 ms	98232 KB	Output is correct
13	Correct	0 ms	340 KB	Output is correct
14	Correct	0 ms	468 KB	Output is correct
15	Correct	1 ms	724 KB	Output is correct
16	Correct	1 ms	1236 KB	Output is correct
17	Correct	1 ms	1236 KB	Output is correct
18	Correct	1 ms	1236 KB	Output is correct
19	Correct	1 ms	1236 KB	Output is correct
20	Correct	1 ms	1236 KB	Output is correct
21	Correct	1 ms	1236 KB	Output is correct
22	Correct	4 ms	8276 KB	Output is correct
23	Correct	2 ms	340 KB	Output is correct
24	Correct	113 ms	98136 KB	Output is correct
25	Correct	74 ms	98120 KB	Output is correct
26	Correct	66 ms	98116 KB	Output is correct
27	Correct	70 ms	98140 KB	Output is correct
28	Correct	68 ms	98140 KB	Output is correct
29	Correct	66 ms	98124 KB	Output is correct
30	Correct	71 ms	98144 KB	Output is correct
31	Correct	68 ms	98164 KB	Output is correct
32	Correct	75 ms	98172 KB	Output is correct