杭电 hdu 2181 哈密顿绕行世界问题-优快云博客

好吧，没什么难度的，只是要注意那个 ‘0’ 的判断我用了控制台函数……这个不会的可以去查资料，百度之，谷歌之……

/* THE PROGRAM IS MADE BY PYY */ /*----------------------------------------------------------------------------// Copyright (c) 2011 panyanyany All rights reserved. URL : http://acm.hdu.edu.cn/showproblem.php?pid=2181 Name : 2181 哈密顿绕行世界问题 Date :Friday，August 12，2011 Time Stage : 1 hours around Result: 4400410 2011-08-12 21:04:56 Accepted 2181 0MS 192K 1475 B C++ pyy Test Data: Review: //----------------------------------------------------------------------------*/ #include <stdio.h> #include <string.h> #define max(a, b) (((a) > (b)) ? (a) : (b)) #define min(a, b) (((a) < (b)) ? (a) : (b)) #define infinity 0x7f7f7f7f #define minus_inf 0x80808080 #define MAXSIZE 21 int way, m ; int city[MAXSIZE][3], route[MAXSIZE], used[MAXSIZE] ; void dfs (int c, int cnt) { int i ; route[cnt] = c ; if (c == m && cnt == 20) { printf ("%d: %d ", way++, m) ; for (i = 1 ; i < 20 ; ++i) printf ("%d ", route[i]) ; printf ("%d\n", route[i]) ; } for (i = 0 ; i < 3 ; ++i) { if (!used[city[c][i]]) { used[city[c][i]] = 1 ; dfs (city[c][i], cnt + 1) ; used[city[c][i]] = 0 ; } } } int main () { char c ; int i ; while (1) { c = getc (stdin) ; // 从输入流中提取一个字符 if (c == '0') break ; ungetc (c, stdin) ; // 把这个字符还回去 for (i = 1 ; i <= 20 ; ++i) scanf ("%d%d%d", &city[i][0], &city[i][1], &city[i][2]) ; scanf ("%d", &m) ; memset (used, 0, sizeof (used)) ; way = 1 ; for (i = 0 ; i < 3 ; ++i) { used[city[m][i]] = 1 ; dfs (city[m][i], 1) ; used[city[m][i]] = 0 ; } getchar () ; // 别忘了吃掉一个多余的回车键 } return 0 ; }