10004 - Bicoloring
Time limit: 3.000 seconds
http://uva.onlinejudge.org/index.php?option=com_onlinejudge&Itemid=8&category=24&page=show_problem&problem=945
In 1976 the ``Four Color Map Theorem" was proven with the assistance of a computer. This theorem states that every map can be colored using only four colors, in such a way that no region is colored using the same color as a neighbor region.
Here you are asked to solve a simpler similar problem. You have to decide whether a given arbitrary connected graph can be bicolored. That is, if one can assign colors (from a palette of two) to the nodes in such a way that no two adjacent nodes have the same color. To simplify the problem you can assume:
no node will have an edge to itself.
the graph is nondirected. That is, if a node a is said to be connected to a node b, then you must assume that b is connected to a.
the graph will be strongly connected. That is, there will be at least one path from any node to any other node.
Input
The input consists of several test cases. Each test case starts with a line containing the number n ( 1 < n< 200) of different nodes. The second line contains the number of edges l. After this, l lines will follow, each containing two numbers that specify an edge between the two nodes that they represent. A node in the graph will be labeled using a number a ( ).
An input with n = 0 will mark the end of the input and is not to be processed.
Output
You have to decide whether the input graph can be bicolored or not, and print it as shown below.
Sample Input
3 3 0 1 1 2 2 0 9 8 0 1 0 2 0 3 0 4 0 5 0 6 0 7 0 8 0
Sample Output
NOT BICOLORABLE. BICOLORABLE.
简单的二分图判定问题,用邻接矩阵算了。
完整代码:
01./*0.025s*/ 02. 03.#include<cstdio> 04.#include<cstring> 05. 06.int a[201][201], vist[202], t[202]; 07.int n, m, p; 08. 09.int dfs() 10.{ 11. for (int i = 0; i < n; i++) 12. for (int j = 0; j < n; j++) 13. if (a[i][j]) 14. { 15. if (t[i] && t[j] && vist[i] == vist[j]) 16. return 0; 17. else if (t[i] && !t[j]) 18. { 19. vist[j] = -vist[i]; 20. t[j] = 1; 21. } 22. else if (!t[i] && t[j]) 23. { 24. vist[i] = -vist[j]; 25. t[i] = 1; 26. } 27. } 28. return 1; 29.} 30. 31.int main(void) 32.{ 33. while (scanf("%d%d", &n, &m), n) 34. { 35. memset(a, 0, sizeof(a)); 36. memset(vist, 0, sizeof(vist)); 37. memset(t, 0, sizeof(t)); 38. for (int i = 0; i < m; i++) 39. { 40. int c, d; 41. scanf("%d%d", &c, &d); 42. a[c][d]++; 43. } 44. vist[0] = 1; 45. t[0] = 1; 46. puts(dfs() ? "BICOLORABLE." : "NOT BICOLORABLE."); 47. } 48. return 0; 49.}
查看本栏目更多精彩内容:http://www.bianceng.cnhttp://www.bianceng.cn/Programming/sjjg/
以上是小编为您精心准备的的内容,在的博客、问答、公众号、人物、课程等栏目也有的相关内容,欢迎继续使用右上角搜索按钮进行搜索int
, at&amp;t汇编语言
, node
, jquery&#39; is undefined
, graph
, 二分图
, Connected
, The
that
10004、程序异常10004、gb t10004、格拉苏蒂10004、gb t10004 2008,以便于您获取更多的相关知识。