oj.uz

Submission #378435

# Submission time Handle Problem Language Result Execution time Memory
378435 2021-03-16T19:03:25 Z rainboy Boat (APIO16_boat) C
9 / 100
 511 ms 512 KB 
#include <stdio.h>

#define N	500
#define MD	1000000007

unsigned int X = 12345;

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

int vv[N + 1], ff[N + 1], gg[N + 1];

void init() {
	int i;

	ff[0] = gg[0] = 1;
	for (i = 1; i <= N; i++) {
		vv[i] = i == 1 ? 1 : (long long) vv[i - MD % i] * (MD / i + 1) % MD;
		ff[i] = (long long) ff[i - 1] * i % MD;
		gg[i] = (long long) gg[i - 1] * vv[i] % MD;
	}
}

int xx[N * 2];

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 (xx[ii[j]] == xx[i_])
				j++;
			else if (xx[ii[j]] < xx[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;
	}
}

long long choose(int n, int k) {
	return (long long) ff[n] * gg[k] % MD * gg[n - k] % MD;
}

int main() {
	static int ii[N * 2], xx_[N * 2], dp[N + 1];
	int n, h, i, j, ans;

	init();
	scanf("%d", &n);
	for (i = 0; i < n; i++) {
		scanf("%d%d", &xx[i << 1 | 0], &xx[i << 1 | 1]);
		xx[i << 1 | 1]++;
	}
	for (i = 0; i < n * 2; i++)
		ii[i] = i;
	sort(ii, 0, n * 2);
	for (i = 0; i < n * 2; i++)
		xx_[i] = xx[ii[i]], xx[ii[i]] = i;
	dp[0] = 1;
	for (h = 0; h + 1 < n * 2; h++) {
		int x = xx_[h + 1] - xx_[h];

		if (x > 0)
		for (j = n; j > 0; j--)
			if (xx[j - 1 << 1 | 0] <= h && h < xx[j - 1 << 1 | 1]) {
				int k;

				k = 0;
				for (i = j - 1; i >= 0; i--)  {
					if (xx[i << 1 | 0] <= h && h < xx[i << 1 | 1])
						k++;
					dp[j] = (dp[j] + dp[i] * choose(k + x - 1, x - 1)) % MD;
				}
			}
	}
	ans = 0;
	for (i = 1; i <= n; i++)
		ans = (ans + dp[i]) % MD;
	printf("%d\n", ans);
	return 0;
}

Compilation message

boat.c: In function 'main':
boat.c:71:13: warning: suggest parentheses around '-' inside '<<' [-Wparentheses]
   71 |    if (xx[j - 1 << 1 | 0] <= h && h < xx[j - 1 << 1 | 1]) {
      |           ~~^~~
boat.c:71:44: warning: suggest parentheses around '-' inside '<<' [-Wparentheses]
   71 |    if (xx[j - 1 << 1 | 0] <= h && h < xx[j - 1 << 1 | 1]) {
      |                                          ~~^~~
boat.c:55:2: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
   55 |  scanf("%d", &n);
      |  ^~~~~~~~~~~~~~~
boat.c:57:3: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
   57 |   scanf("%d%d", &xx[i << 1 | 0], &xx[i << 1 | 1]);
      |   ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

Subtask #1
9.0 / 9.0

# Verdict Execution time Memory Grader output
1 Correct 3 ms 364 KB Output is correct
2 Correct 3 ms 384 KB Output is correct
3 Correct 3 ms 364 KB Output is correct
4 Correct 3 ms 364 KB Output is correct
5 Correct 3 ms 364 KB Output is correct
6 Correct 2 ms 384 KB Output is correct
7 Correct 4 ms 492 KB Output is correct
8 Correct 3 ms 364 KB Output is correct
9 Correct 3 ms 364 KB Output is correct
10 Correct 2 ms 364 KB Output is correct
11 Correct 2 ms 364 KB Output is correct
12 Correct 2 ms 364 KB Output is correct
13 Correct 3 ms 384 KB Output is correct
14 Correct 2 ms 364 KB Output is correct
15 Correct 2 ms 364 KB Output is correct
16 Correct 2 ms 364 KB Output is correct
17 Correct 2 ms 364 KB Output is correct
18 Correct 2 ms 364 KB Output is correct
19 Correct 2 ms 364 KB Output is correct
20 Correct 2 ms 364 KB Output is correct

Subtask #2
0 / 22.0

# Verdict Execution time Memory Grader output
1 Correct 3 ms 364 KB Output is correct
2 Correct 3 ms 384 KB Output is correct
3 Correct 3 ms 364 KB Output is correct
4 Correct 3 ms 364 KB Output is correct
5 Correct 3 ms 364 KB Output is correct
6 Correct 2 ms 384 KB Output is correct
7 Correct 4 ms 492 KB Output is correct
8 Correct 3 ms 364 KB Output is correct
9 Correct 3 ms 364 KB Output is correct
10 Correct 2 ms 364 KB Output is correct
11 Correct 2 ms 364 KB Output is correct
12 Correct 2 ms 364 KB Output is correct
13 Correct 3 ms 384 KB Output is correct
14 Correct 2 ms 364 KB Output is correct
15 Correct 2 ms 364 KB Output is correct
16 Correct 2 ms 364 KB Output is correct
17 Correct 2 ms 364 KB Output is correct
18 Correct 2 ms 364 KB Output is correct
19 Correct 2 ms 364 KB Output is correct
20 Correct 2 ms 364 KB Output is correct
21 Correct 376 ms 512 KB Output is correct
22 Correct 364 ms 492 KB Output is correct
23 Correct 339 ms 492 KB Output is correct
24 Correct 365 ms 364 KB Output is correct
25 Correct 367 ms 364 KB Output is correct
26 Incorrect 511 ms 492 KB Output isn't correct
27 Halted 0 ms 0 KB -

Subtask #3
0 / 27.0

# Verdict Execution time Memory Grader output
1 Runtime error 1 ms 364 KB Execution killed with signal 11
2 Halted 0 ms 0 KB -

Subtask #4
0 / 42.0

# Verdict Execution time Memory Grader output
1 Correct 3 ms 364 KB Output is correct
2 Correct 3 ms 384 KB Output is correct
3 Correct 3 ms 364 KB Output is correct
4 Correct 3 ms 364 KB Output is correct
5 Correct 3 ms 364 KB Output is correct
6 Correct 2 ms 384 KB Output is correct
7 Correct 4 ms 492 KB Output is correct
8 Correct 3 ms 364 KB Output is correct
9 Correct 3 ms 364 KB Output is correct
10 Correct 2 ms 364 KB Output is correct
11 Correct 2 ms 364 KB Output is correct
12 Correct 2 ms 364 KB Output is correct
13 Correct 3 ms 384 KB Output is correct
14 Correct 2 ms 364 KB Output is correct
15 Correct 2 ms 364 KB Output is correct
16 Correct 2 ms 364 KB Output is correct
17 Correct 2 ms 364 KB Output is correct
18 Correct 2 ms 364 KB Output is correct
19 Correct 2 ms 364 KB Output is correct
20 Correct 2 ms 364 KB Output is correct
21 Correct 376 ms 512 KB Output is correct
22 Correct 364 ms 492 KB Output is correct
23 Correct 339 ms 492 KB Output is correct
24 Correct 365 ms 364 KB Output is correct
25 Correct 367 ms 364 KB Output is correct
26 Incorrect 511 ms 492 KB Output isn't correct
27 Halted 0 ms 0 KB -