Submission #745327

#	Submission time	Handle	Problem	Language	Result	Execution time	Memory
745327	2023-05-19T21:14:14 Z	rainboy	Exam (eJOI20_exam)	C	100 / 100	110 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;
}

int aa[N];

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 (aa[ii[j]] == aa[i_])
				j++;
			else if (aa[ii[j]] < aa[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 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:58:2: warning: ignoring return value of 'scanf' declared with attribute 'warn_unused_result' [-Wunused-result]
   58 |  scanf("%d", &n);
      |  ^~~~~~~~~~~~~~~
exam.c:60:3: warning: ignoring return value of 'scanf' declared with attribute 'warn_unused_result' [-Wunused-result]
   60 |   scanf("%d", &aa[i]);
      |   ^~~~~~~~~~~~~~~~~~~
exam.c:62:3: warning: ignoring return value of 'scanf' declared with attribute 'warn_unused_result' [-Wunused-result]
   62 |   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	340 KB	Output is correct
3	Correct	1 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	1 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	9 ms	340 KB	Output is correct
3	Correct	18 ms	980 KB	Output is correct
4	Correct	17 ms	980 KB	Output is correct
5	Correct	26 ms	1024 KB	Output is correct
6	Correct	21 ms	996 KB	Output is correct
7	Correct	20 ms	988 KB	Output is correct
8	Correct	28 ms	1068 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	14 ms	23892 KB	Output is correct
4	Correct	68 ms	94280 KB	Output is correct
5	Correct	64 ms	98208 KB	Output is correct
6	Correct	71 ms	98136 KB	Output is correct

Subtask #4

23.0 / 23.0

#	Verdict	Execution time	Memory	Grader output
1	Correct	3 ms	440 KB	Output is correct
2	Correct	25 ms	1920 KB	Output is correct
3	Correct	67 ms	3532 KB	Output is correct
4	Correct	66 ms	4336 KB	Output is correct
5	Correct	75 ms	4892 KB	Output is correct
6	Correct	56 ms	3944 KB	Output is correct
7	Correct	60 ms	4760 KB	Output is correct
8	Correct	75 ms	3684 KB	Output is correct
9	Correct	63 ms	3776 KB	Output is correct
10	Correct	46 ms	3916 KB	Output is correct

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	340 KB	Output is correct
3	Correct	1 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	1 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	340 KB	Output is correct
3	Correct	1 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	1 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	14 ms	23892 KB	Output is correct
10	Correct	68 ms	94280 KB	Output is correct
11	Correct	64 ms	98208 KB	Output is correct
12	Correct	71 ms	98136 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	5 ms	8276 KB	Output is correct
23	Correct	2 ms	340 KB	Output is correct
24	Correct	110 ms	98184 KB	Output is correct
25	Correct	72 ms	98108 KB	Output is correct
26	Correct	66 ms	98244 KB	Output is correct
27	Correct	69 ms	98212 KB	Output is correct
28	Correct	66 ms	98220 KB	Output is correct
29	Correct	65 ms	98132 KB	Output is correct
30	Correct	68 ms	98120 KB	Output is correct
31	Correct	67 ms	98160 KB	Output is correct
32	Correct	67 ms	98188 KB	Output is correct