zoukankan      html  css  js  c++  java
  • Courses

    Courses

    Time Limit: 20000/10000 MS (Java/Others)    Memory Limit: 65536/32768 K (Java/Others)
    Total Submission(s): 2681    Accepted Submission(s): 1238

    Problem Description
    Consider a group of N students and P courses. Each student visits zero, one or more than one courses. Your task is to determine whether it is possible to form a committee of exactly P students that satisfies simultaneously the conditions:

    . every student in the committee represents a different course (a student can represent a course if he/she visits that course)

    . each course has a representative in the committee

    Your program should read sets of data from a text file. The first line of the input file contains the number of the data sets. Each data set is presented in the following format:

    P N
    Count1 Student1 1 Student1 2 ... Student1 Count1
    Count2 Student2 1 Student2 2 ... Student2 Count2
    ......
    CountP StudentP 1 StudentP 2 ... StudentP CountP

    The first line in each data set contains two positive integers separated by one blank: P (1 <= P <= 100) - the number of courses and N (1 <= N <= 300) - the number of students. The next P lines describe in sequence of the courses . from course 1 to course P, each line describing a course. The description of course i is a line that starts with an integer Count i (0 <= Count i <= N) representing the number of students visiting course i. Next, after a blank, you'll find the Count i students, visiting the course, each two consecutive separated by one blank. Students are numbered with the positive integers from 1 to N.

    There are no blank lines between consecutive sets of data. Input data are correct.

    The result of the program is on the standard output. For each input data set the program prints on a single line "YES" if it is possible to form a committee and "NO" otherwise. There should not be any leading blanks at the start of the line.

    An example of program input and output:
     

    Sample Input
    2
    3 3
    3 1 2 3
    2 1 2
    1 1
    3 3
    2 1 3
    2 1 3
    1 1
     

    Sample Output
    YES
    NO
     

    Source
    Southeastern Europe 2000

    #include<stdio.h>
    #include<string.h>
    int P,N;
    bool G[400][400],visit[400];
    int match[400];
    bool DFS(int k)
    {
        int t;
        for (int i=1;i<=N;i++)
        if (G[k][i] && !visit[i])
        {
            visit[i]=1;
            t=match[i];
            match[i]=k;
            if (t==-1 || DFS(t)) return true;
            match[i]=t;
        }
        return false;
    }
    int Max_match()
    {
        int ans=0;
        memset(match,-1,sizeof(match));
        for (int i=1;i<=P;i++)
        {
            memset(visit,0,sizeof(visit));
            if (DFS(i)) ans++;
        }
        return ans;
    }
    int main()
    {
        int T;
        scanf("%d",&T);
        while (T--)
        {
            memset(G,0,sizeof(G));
            scanf("%d%d",&P,&N);
            for (int i=1;i<=P;i++)
            {
                int cp;
                scanf("%d",&cp);
                for (int j=1;j<=cp;j++)
                {
                    int x;
                    scanf("%d",&x);
                    G[i][x]=1;
                }
            }
            if (Max_match()==P) printf("YES
    ");
            else printf("NO
    ");
        }
        return 0;
    }
  • 相关阅读:
    input 框变成不可编辑的。
    git 首次往远程仓库提交项目过程。(使用idea操作)
    nacos 导入项目配置(yml文件)步骤
    instr MySQL数据库函数用法
    遍历 map 的方法
    基于分布式思想下的rpc解决方案(1)
    深入理解通信协议-(1)
    Tomcat(3)--性能优化
    并发编程(5)--并发容器
    并发编程(4)--显示锁和AQS
  • 原文地址:https://www.cnblogs.com/dramstadt/p/3193369.html
Copyright © 2011-2022 走看看