zoukankan      html  css  js  c++  java
  • hduoj-----(1068)Girls and Boys(二分匹配)

    Girls and Boys

    Time Limit: 20000/10000 MS (Java/Others)    Memory Limit: 65536/32768 K (Java/Others)
    Total Submission(s): 7577    Accepted Submission(s): 3472


    Problem Description
    the second year of the university somebody started a study on the romantic relations between the students. The relation “romantically involved” is defined between one girl and one boy. For the study reasons it is necessary to find out the maximum set satisfying the condition: there are no two students in the set who have been “romantically involved”. The result of the program is the number of students in such a set.

    The input contains several data sets in text format. Each data set represents one set of subjects of the study, with the following description:

    the number of students
    the description of each student, in the following format
    student_identifier:(number_of_romantic_relations) student_identifier1 student_identifier2 student_identifier3 ...
    or
    student_identifier:(0)

    The student_identifier is an integer number between 0 and n-1, for n subjects.
    For each given data set, the program should write to standard output a line containing the result.
     
    Sample Input
    7 0: (3) 4 5 6 1: (2) 4 6 2: (0) 3: (0) 4: (2) 0 1 5: (1) 0 6: (2) 0 1 3 0: (2) 1 2 1: (1) 0 2: (1) 0
     
    Sample Output
    5 2
    Source
     
     
    题意大致为: 有一个学校,男生女生要搭配,然后排除男神和男生搞基,女生和女生玩拉拉的意思,问最少有多少个落单的倒霉求?
     
    其实就是变相的,最大匹配,就是求出了最大匹配,然后剩下的那些个倒霉求就是所求的答案嘛.....
     
     
    代码:
     1 #include<cstring>
     2 #include<cstdio>
     3 #include<cstdlib>
     4 using namespace std;
     5 const int maxn=1005;
     6 int n,a,b,c;
     7 bool mat[maxn][maxn];
     8 bool vis[maxn];
     9 int girl[maxn];
    10 bool check(int x){
    11     for(int i=0;i<n;i++){
    12         if(mat[x][i]==1&&!vis[i]){
    13             vis[i]=1;
    14             if(girl[i]==-1||check(girl[i])){
    15               girl[i]=x;
    16                return 1;
    17             }
    18         }
    19     }
    20     return 0;
    21 }
    22 int main()
    23 {
    24     //freopen("test.in","r",stdin);
    25     while(scanf("%d",&n)!=EOF){
    26         memset(mat,0,sizeof(mat));
    27         memset(girl,-1,sizeof(girl));
    28         for(int i=0;i<n;i++){
    29           scanf("%d: (%d)",&a,&b);
    30           while(b--){
    31               scanf("%d",&c);
    32               mat[a][c]=1;
    33           }
    34         }
    35         int ans=0;
    36         for(int j=0;j<n;j++){
    37             memset(vis,0,sizeof(vis));
    38             if(check(j))ans++;
    39         }
    40     /*通过最大二分匹配,我们得到了最大匹配数,但是由于男生女生
    41     都算了一遍,所以是不是就得除以二。这样就是最大匹配数了*/
    42         printf("%d
    ",n-ans/2);
    43     }
    44   return 0;
    45 }
    View Code
     
  • 相关阅读:
    [JavaScript权威指南]Introduce to JavaScript
    IT项目开发的75条管理守则
    .net调用存储过程
    应聘项目经理需要学的
    DropDownList静态数据绑定
    数据库的查询优化技术 (摘)
    UNION运算符
    网站项目策划书
    .net验证码
    小问题,关于Page.Request.QueryString["pro"]
  • 原文地址:https://www.cnblogs.com/gongxijun/p/3927936.html
Copyright © 2011-2022 走看看