杭电 hdu 1856 More is better （并查集）

/* THE PROGRAM IS MADE BY PYY */ /*----------------------------------------------------------------------------// Copyright (c) 2011 panyanyany All rights reserved. URL : http://acm.hdu.edu.cn/showproblem.php?pid=1856 Name : 1856 More is better Date : Monday, August 29, 2011 Time Stage : half hour Result: 4512304 2011-08-29 19:39:07 Accepted 1856 265MS 78584K 1213 B C++ pyy 4512286 2011-08-29 19:37:01 Wrong Answer 1856 265MS 78584K 1213 B C++ pyy Test Data: Review: 其实也挺简单的，只不过数据有点大，以及res要初始化 为1，因为最少都有一个boy，所以当n=0的时候，res就输出1 //----------------------------------------------------------------------------*/ #include #include #define max(a, b) ((a) > (b) ? (a) : (b)) #define MAXSIZE 10000009 int n, res ; typedef struct tagNODE { int cnt, prn ; } NODE ; NODE ufSet[MAXSIZE] ; int find (int x) { int tmp ; if (ufSet[x].prn != x) ufSet[x].prn = find (ufSet[x].prn) ; return ufSet[x].prn ; } void merge (int px, int py) { ufSet[py].prn = px ; ufSet[px].cnt += ufSet[py].cnt ; ufSet[py].cnt = 1 ; res = max (res, ufSet[px].cnt) ; } int main () { int i, j ; int x, y, px, py ; while (scanf ("%d", &n) != EOF) { res = 1 ; for (i = 1 ; i < MAXSIZE ; ++i) { ufSet[i].prn = i ; ufSet[i].cnt = 1 ; } for (i = 0 ; i < n ; ++i) { scanf ("%d%d", &x, &y) ; px = find (x) ; py = find (y) ; if (px != py) merge (px, py) ; } printf ("%d\n", res) ; } return 0 ; }