prog_1.1-quick_find.c

#include <stdio.h>
#define N 10000

main()
{
	int i, p, q, t, id[N];
	for (i = 0; i < N; i++)
		id[i] = i;
	while (scanf("%d %d\n", &p, &q) == 2)
	{	
		if (id[p] == id[q])
			continue;
		for (t = id[p], i = 0; i < N; i++)
			if (id[i] == t)
				id[i] = id[q];
		printf(" %d %d\n", p, q);
	}
}