zoukankan      html  css  js  c++  java
  • Circles of Friends

    A circle of friends is a network of friend relationships. If A is a friend of B, then B is considered a friend of A no matter B admits or not, and they are said to belong to the same circle. Here we assume that friendship is transitive, that is, if A is a friend of B, and B is a friend of C, then A is a friend of C and the three of them all belong to the same circle.

    On the other hand, A is not so close to C as B is. We define the distance D(X, Y) between two friends X and Y as the minimum number of friends between them. For example, D(A, B) = 0, and D(C, A) = 1. The diameter of a friends circle is the maximum distance between any pair of friends in the circle.

    Now given some people's relationships, you are supposed to find the number of friends circles and the circle with the largest diameter.

    Input Specification:

    Each input file contains one test case. For each case, the first line gives an integer N (2), which is the total number of people involved, and hence they are numbered from 1 to N. Then N lines follow, each in the format:

    p1​​ ... pk​​

    where k (0) is the number of friends and p1​​ to pk​​ (if k>0) are the friends' indices. The i-th line corresponds to the i-th person. All the numbers in a line are separated by spaces. It is guaranteed that no one is given as a friend of oneself.

    Output Specification:

    For each case, print in a line the number of friends circles, and the largest diameter, separated by exactly one space.

    Sample Input:

    17
    2 15 12
    1 17
    2 16 9
    1 8
    4 10 13 15 14
    0
    2 11 14
    1 4
    2 2 3
    2 13 11
    2 15 7
    2 1 14
    2 5 15
    0
    0
    1 3
    1 2
    
     

    Sample Output:

    4 3
     1 #include<bits/stdc++.h>
     2 using namespace std;
     3 vector<set<int> > v;
     4 vector<bool> vb;
     5 vector<int> vr;
     6 set<int>::iterator its;
     7 int spart,smax;
     8 void bfs(int n,bool flag)
     9 {
    10     vector<bool> vbb(vb.size(),true);
    11     int md=0;
    12     pair<int,int> p;
    13     queue<pair<int,int> > q;
    14     q.push(pair<int,int>(n,-1));
    15     if(flag)
    16     vb[n]=false;
    17     else
    18     vbb[n]=false;
    19     for(;!q.empty();q.pop())
    20     {
    21         p=q.front();
    22         if(p.second>md)
    23         {
    24             md=p.second;
    25             if(flag)
    26             {
    27                 vr.clear();
    28                 vr.push_back(p.first);
    29             }
    30         }
    31         else if(p.second==md)
    32         if(flag)
    33         vr.push_back(p.first);
    34         for(its=v[p.first].begin();its!=v[p.first].end();++its)
    35         {
    36             if(flag)
    37             {
    38                 if(vb[*its])
    39                 {
    40                     vb[*its]=false;
    41                     q.push(pair<int,int>(*its,p.second+1));
    42                 }
    43             }
    44             else
    45             {
    46                 if(vbb[*its])
    47                 {
    48                     vbb[*its]=false;
    49                     q.push(pair<int,int>(*its,p.second+1));
    50                 }
    51             }
    52         }
    53     }
    54     if(md>smax)
    55     smax=md;
    56     return;
    57 }
    58 int main()
    59 {
    60 //    ios::sync_with_stdio(false);
    61  //     freopen("data.txt","r",stdin);
    62       int n,k,x;
    63       spart=0,smax=0;
    64       scanf("%d",&n);
    65       v.resize(n);
    66       vb.resize(n,true);
    67       for(int i=0;i<n;i++)
    68       {
    69           scanf("%d",&k);
    70           for(;k--;)
    71           {
    72               scanf("%d",&x);
    73               x--;
    74             v[i].insert(x);
    75             v[x].insert(i);
    76         }
    77     }
    78     for(int t=0;t<v.size();t++)
    79     {
    80         if(vb[t])
    81         {
    82             bfs(t,true);
    83             for(int i=0;i<vr.size();i++)
    84             bfs(vr[i],false);
    85             spart++;
    86             t=0;
    87         }
    88     }
    89     printf("%d %d",spart,smax);
    90 
    91     return 0;
    92 }
    诚者,君子之所守也。
  • 相关阅读:
    Log4Qt 使用(一)
    “定义为指针,外部以数组形式引用”和“定义为数组,外部以指针形式引用”会发生什么?
    gcc总结【基本用法】【选项】【动静态库】(转)
    C++沉思录之三——设计容器类
    C++沉思录之二——虚函数使用的时机
    何时需要自定义复制构造函数?
    C++沉思录之一
    搜索百度云里面的内容技巧
    Qt 之容器内的控件全屏
    python的代码检查
  • 原文地址:https://www.cnblogs.com/SkystarX/p/12285794.html
Copyright © 2011-2022 走看看