杭电 hdu 1213 How Many Tables （并查集，简单题）

/* THE PROGRAM IS MADE BY PYY */ /*----------------------------------------------------------------------------// Copyright (c) 2011 panyanyany All rights reserved. URL : http://acm.hdu.edu.cn/showproblem.php?pid=1213 Name : 1213 How Many Tables Date : Sunday, September 04, 2011 Time Stage : half an hour Result: 4541434 2011-09-04 14:28:07 Accepted 1213 0MS 192K 1230 B C++ pyy Test Data : Review : 很裸的并查集……水题 //----------------------------------------------------------------------------*/ #include <stdio.h> #include <string.h> #define max(a, b) ((a) > (b) ? (a) : (b)) #define min(a, b) ((a) < (b) ? (a) : (b)) #define MAXSIZE (1009) int tcase, n, m ; int ufSet[MAXSIZE] ; int find (int x) { if (x != ufSet[x]) ufSet[x] = find (ufSet[x]) ; return ufSet[x] ; } void merge (int pa, int pb) { ufSet[pb] = pa ; } int main () { int i, j ; int a, b, pa, pb ; int cnt ; while (scanf ("%d", &tcase) != EOF) { while (tcase--) { for (i = 1 ; i < MAXSIZE ; ++i) ufSet[i] = i ; scanf ("%d%d", &n, &m) ; for (i = 1 ; i <= m ; ++i) { scanf ("%d%d", &a, &b) ; pa = find (a) ; pb = find (b) ; if (pa != pb) merge (pa, pb) ; } cnt = 0 ; for (i = 1 ; i <= n ; ++i) if (find (i) == i) ++cnt ; printf ("%d\n", cnt) ; } } return 0 ; }