Submission #493280

#	Time	Username	Problem	Language	Result	Execution time	Memory
493280		rainboy	Cigle (COI21_cigle)	C11	100 / 100	263 ms	67404 KiB

cigle

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

#define N	5000

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

int main() {
	static int aa[N + 1], dp[N + 1][N + 1], dq[N + 1];
	int n, i, j, k, x, c, ans;

	scanf("%d", &n);
	for (i = 1; i <= n; i++) {
		scanf("%d", &aa[i]);
		aa[i] += aa[i - 1];
	}
	for (i = 1; i <= n; i++)
		dp[0][i] = 0;
	for (j = 1; j <= n; j++) {
		for (i = 0; i < j; i++)
			dq[i] = dp[i][j];
		for (i = 1; i < j; i++)
			dq[i] = max(dq[i], dq[i - 1]);
		x = 0, c = 0;
		for (i = j - 1, k = j + 1; k <= n; k++) {
			dp[j][k] = x;
			while (i >= 0 && aa[i] + aa[k] > aa[j] * 2)
				i--;
			if (i > 0 && aa[i] + aa[k] == aa[j] * 2)
				x = max(x, dq[i - 1] + ++c);
		}
	}
	ans = 0;
	for (i = 0; i < n; i++)
		ans = max(ans, dp[i][n]);
	printf("%d\n", ans);
	return 0;
}

Compilation message (stderr)

cigle.c: In function 'main':
cigle.c:12:2: warning: ignoring return value of 'scanf' declared with attribute 'warn_unused_result' [-Wunused-result]
   12 |  scanf("%d", &n);
      |  ^~~~~~~~~~~~~~~
cigle.c:14:3: warning: ignoring return value of 'scanf' declared with attribute 'warn_unused_result' [-Wunused-result]
   14 |   scanf("%d", &aa[i]);
      |   ^~~~~~~~~~~~~~~~~~~

• Subtask 1: 9 / 9
• Subtask 2: 11 / 11
• Subtask 3: 13 / 13
• Subtask 4: 15 / 15
• Subtask 5: 52 / 52