Submission #829487

#	Time	Username	Problem	Language	Result	Execution time	Memory
829487		rainboy	Curtains (NOI23_curtains)	C11	24 / 100	176 ms	18288 KiB

curtains

#include <stdio.h>

#define N	2000
#define M	500000

int main() {
	static char has[N][N], can[N][N];
	static int ll[N], qu[N];
	int n, m, q, cnt, l, r;

	scanf("%d%d%d", &n, &m, &q);
	while (m--) {
		scanf("%d%d", &l, &r), l--, r--;
		has[l][r] = 1;
	}
	for (r = 0; r < n; r++)
		ll[r] = r + 1;
	for (l = n - 1; l >= 0; l--) {
		for (r = l; r < n; r++)
			if (has[l][r])
				ll[r] = l;
		cnt = 0;
		for (r = l; r < n; r++) {
			qu[cnt++] = r;
			while (cnt && qu[cnt - 1] >= ll[r])
				cnt--;
			can[l][r] = cnt == 0;
		}
	}
	while (q--) {
		scanf("%d%d", &l, &r), l--, r--;
		printf(can[l][r] ? "YES\n" : "NO\n");
	}
	return 0;
}

Compilation message (stderr)

curtains.c: In function 'main':
curtains.c:11:2: warning: ignoring return value of 'scanf' declared with attribute 'warn_unused_result' [-Wunused-result]
   11 |  scanf("%d%d%d", &n, &m, &q);
      |  ^~~~~~~~~~~~~~~~~~~~~~~~~~~
curtains.c:13:3: warning: ignoring return value of 'scanf' declared with attribute 'warn_unused_result' [-Wunused-result]
   13 |   scanf("%d%d", &l, &r), l--, r--;
      |   ^~~~~~~~~~~~~~~~~~~~~
curtains.c:31:3: warning: ignoring return value of 'scanf' declared with attribute 'warn_unused_result' [-Wunused-result]
   31 |   scanf("%d%d", &l, &r), l--, r--;
      |   ^~~~~~~~~~~~~~~~~~~~~

• Subtask 1: 3 / 3
• Subtask 2: 6 / 6
• Subtask 3: 15 / 15
• Subtask 4: 0 / 20
• Subtask 5: 0 / 36
• Subtask 6: 0 / 20