Submission #500633

#	Time	Username	Problem	Language	Result	Execution time	Memory
500633		rainboy	Tortoise (CEOI21_tortoise)	C11	18 / 100	18 ms	1316 KiB

tortoise

#include <stdio.h>
#include <string.h>

#define N	300
#define INF	0x3f3f3f3f

int abs_(int a) { return a > 0 ? a : -a; }
int min(int a, int b) { return a < b ? a : b; }
int max(int a, int b) { return a > b ? a : b; }

int main() {
	static int aa[N], dp[N][N * 2];
	static int tt[N][N];
	int n, i, j, k, t;
	long long ans;

	scanf("%d", &n);
	for (i = 0; i < n; i++)
		scanf("%d", &aa[i]);
	for (i = 0; i < n; i++)
		for (j = i + 1; j < n; j++)
			if (aa[i] != -1 && aa[j] != -1) {
				tt[i][j] = INF;
				for (k = 0; k < n; k++)
					if (aa[k] == -1)
						tt[i][j] = min(tt[i][j], abs_(i - k) + abs_(k - j));
			}
	for (i = 0; i < n; i++)
		memset(dp[i], -1, n * 2 * sizeof *dp[i]);
	ans = 0;
	for (i = 0; i < n; i++)
		if (aa[i] == 1) {
			dp[i][i] = max(dp[i][i], 1);
			for (t = 0; t <= i * 2; t++) {
				int x = dp[i][t];

				if (x == -1)
					continue;
				ans = max(ans, x);
				for (j = i + 1; j < n; j++)
					if (aa[j] == 1) {
						int t_ = t + tt[i][j];

						if (t_ <= j * 2)
							dp[j][t_] = max(dp[j][t_], dp[i][t] + 1);
					}
			}
		}
	ans = -ans;
	for (i = 0; i < n; i++)
		if (aa[i] > 0)
			ans += aa[i];
	printf("%lld\n", ans);
	return 0;
}

Compilation message (stderr)

tortoise.c: In function 'main':
tortoise.c:17:2: warning: ignoring return value of 'scanf' declared with attribute 'warn_unused_result' [-Wunused-result]
   17 |  scanf("%d", &n);
      |  ^~~~~~~~~~~~~~~
tortoise.c:19:3: warning: ignoring return value of 'scanf' declared with attribute 'warn_unused_result' [-Wunused-result]
   19 |   scanf("%d", &aa[i]);
      |   ^~~~~~~~~~~~~~~~~~~

• Subtask 1: 8 / 8
• Subtask 2: 10 / 10
• Subtask 3: 0 / 30
• Subtask 4: 0 / 25
• Subtask 5: 0 / 27