제출 #710792

#	제출 시각	아이디	문제	언어	결과	실행 시간	메모리
710792		rainboy	Skyscraper (JOI16_skyscraper)	C11	100 / 100	171 ms	3432 KiB

skyscraper

#include <stdio.h>

#define N	100
#define L	1000
#define MD	1000000007

unsigned int X = 12345;

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

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

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

int main() {
	static int aa[N], dp[N + 1][L + 1][2][2], dq[N + 1][L + 1][2][2];
	int n, l, i, c, d, d_, s, t, a, ans;

	scanf("%d%d", &n, &l);
	if (n == 1) {
		printf("1\n");
		return 0;
	}
	for (i = 0; i < n; i++)
		scanf("%d", &aa[i]);
	sort(aa, 0, n);
	dp[0][0][0][0] = 1;
	for (i = 0; i + 1 < n; i++) {
		for (c = 0; c <= n; c++)
			for (d = 0; d <= l; d++)
				for (s = 0; s < 2; s++)
					for (t = 0; t < 2; t++)
						dq[c][d][s][t] = 0;
		for (c = 0; c <= n; c++)
			for (d = 0; d <= l; d++)
				for (s = 0; s < 2; s++)
					for (t = 0; t < 2; t++) {
						int x = dp[c][d][s][t];

						if (x == 0)
							continue;
						dq[c + 1][d][s][t] = (dq[c + 1][d][s][t] + x) % MD;
						if (s == 0)
							dq[c + 1][d][1][t] = (dq[c + 1][d][1][t] + x) % MD;
						if (t == 0)
							dq[c + 1][d][s][1] = (dq[c + 1][d][s][1] + x) % MD;
						dq[c][d][s][t] = (dq[c][d][s][t] + (long long) x * (c * 2 - s - t)) % MD;
						if (s == 0)
							dq[c][d][1][t] = (dq[c][d][1][t] + (long long) x * (c - t)) % MD;
						if (t == 0)
							dq[c][d][s][1] = (dq[c][d][s][1] + (long long) x * (c - s)) % MD;
						if (c > 0)
							dq[c - 1][d][s][t] = (dq[c - 1][d][s][t] + (long long) x * ((c - s - t) * (c - s - t - 1) + (c - s - t) * (s + t))) % MD;
					}
		a = aa[i + 1] - aa[i];
		for (c = 0; c <= n; c++)
			for (d = 0; d <= l; d++)
				for (s = 0; s < 2; s++)
					for (t = 0; t < 2; t++)
						if (s + t <= c * 2) {
							d_ = a * (c * 2 - s - t);
							dp[c][d][s][t] = d < d_ ? 0 : dq[c][d - d_][s][t];
						}
	}
	ans = 0;
	for (d = 0; d <= l; d++)
		ans = ((long long) ans + dp[1][d][1][0] + dp[1][d][0][1] + dp[2][d][1][1]) % MD;
	printf("%d\n", ans);
	return 0;
}

컴파일 시 표준 에러 (stderr) 메시지

skyscraper.c: In function 'main':
skyscraper.c:36:2: warning: ignoring return value of 'scanf' declared with attribute 'warn_unused_result' [-Wunused-result]
   36 |  scanf("%d%d", &n, &l);
      |  ^~~~~~~~~~~~~~~~~~~~~
skyscraper.c:42:3: warning: ignoring return value of 'scanf' declared with attribute 'warn_unused_result' [-Wunused-result]
   42 |   scanf("%d", &aa[i]);
      |   ^~~~~~~~~~~~~~~~~~~

• Subtask 1: 5 / 5
• Subtask 2: 15 / 15
• Subtask 3: 80 / 80