Submission #450427

#	Time	Username	Problem	Language	Result	Execution time	Memory
450427		rainboy	Ronald (COCI17_ronald)	C11	120 / 120	60 ms	3144 KiB

ronald

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

#define N	1000

int ds[N * 2];

int find(int i) {
	return ds[i] < 0 ? i : (ds[i] = find(ds[i]));
}

void join(int i, int j) {
	i = find(i);
	j = find(j);
	if (i == j)
		return;
	if (ds[i] > ds[j])
		ds[i] = j;
	else {
		if (ds[i] == ds[j])
			ds[i]--;
		ds[j] = i;
	}
}

int main() {
	static char adj[N][N];
	int n, m, i, j;

	scanf("%d%d", &n, &m);
	memset(ds, -1, n * 2 * sizeof *ds);
	while (m--) {
		scanf("%d%d", &i, &j), i--, j--;
		adj[i][j] = adj[j][i] = 1;
	}
	for (i = 0; i < n; i++)
		for (j = i + 1; j < n; j++)
			if (adj[i][j])
				join(i << 1 | 0, j << 1 | 0), join(i << 1 | 1, j << 1 | 1);
			else
				join(i << 1 | 0, j << 1 | 1), join(i << 1 | 1, j << 1 | 0);
	printf(find(0 << 1 | 0) == find(0 << 1 | 1) ? "NE\n" : "DA\n");
	return 0;
}

Compilation message (stderr)

ronald.c: In function 'main':
ronald.c:30:2: warning: ignoring return value of 'scanf' declared with attribute 'warn_unused_result' [-Wunused-result]
   30 |  scanf("%d%d", &n, &m);
      |  ^~~~~~~~~~~~~~~~~~~~~
ronald.c:33:3: warning: ignoring return value of 'scanf' declared with attribute 'warn_unused_result' [-Wunused-result]
   33 |   scanf("%d%d", &i, &j), i--, j--;
      |   ^~~~~~~~~~~~~~~~~~~~~

• Subtask 1: 15 / 15
• Subtask 2: 15 / 15
• Subtask 3: 15 / 15
• Subtask 4: 15 / 15
• Subtask 5: 15 / 15
• Subtask 6: 15 / 15
• Subtask 7: 15 / 15
• Subtask 8: 15 / 15