HDU 3172 Virtual Friends (并查集与map的运用，同HDU1829)

#include <stdio.h>
#include <iostream>
#include <map>
using namespace std;

int ff[100005];//ff[x]表示x的父节点
int ss[100005];//

void ii(int n)    //初始化
{
for(int i=1;i<=n;i++)
{
ff[i]=i;
ss[i]=1;
}
}

int dd(int x)    //带路径压缩的查找
{
if(x!=ff[x])
ff[x]=dd(ff[x]);
return ff[x];
}

void cc(int a,int b)    //合并
{
int ta=dd(a);
int tb=dd(b);
if(ta!=tb)
{
ff[ta] = tb;
ss[tb] += ss[ta];
printf("%d\n",ss[tb]);
}
else
printf("%d\n",ss[tb]);
}

int main()
{
int i,t,k,j,N;
int count,max=0,ans;
char a[25];
char b[25];

map<string,int> m;

while(~scanf("%d",&t))
{
while(t--)
{
scanf("%d",&N);
ii(100005);
m.clear();
ans=1;

for(i=1;i<=N;i++)
{
scanf("%s%s",a,b);
if(!m[a])
m[a]=ans++;
if(!m)
m[b]=ans++;
cc(m[a],m[b]);
}
}
}
return 0;
}

关键是：如何将字符串与数字联合起来，想了很久不知道怎么下手，看结题报告才知道用map可以，顺便复习一下map。此题和1829基本上差不多的！！

自己编译器无法编译成功，可能是编译器的问题，提交时AC的。

Virtual Friends

[b]Time Limit: 4000/2000 MS (Java/Others) Memory Limit: 32768/32768 K (Java/Others)

Total Submission(s): 6098 Accepted Submission(s): 1727



Problem Description

These days, you can do all sorts of things online. For example, you can use various websites to make virtual friends. For some people, growing their social network (their friends, their friends' friends, their friends' friends' friends, and so on), has become
an addictive hobby. Just as some people collect stamps, other people collect virtual friends.

Your task is to observe the interactions on such a website and keep track of the size of each person's network.

Assume that every friendship is mutual. If Fred is Barney's friend, then Barney is also Fred's friend.

Input

Input file contains multiple test cases.

The first line of each case indicates the number of test friendship nest.

each friendship nest begins with a line containing an integer F, the number of friendships formed in this frindship nest, which is no more than 100 000. Each of the following F lines contains the names of two people who have just become friends, separated by
a space. A name is a string of 1 to 20 letters (uppercase or lowercase).

Output

Whenever a friendship is formed, print a line containing one integer, the number of people in the social network of the two people who have just become friends.

Sample Input

1
3
Fred Barney
Barney Betty
Betty Wilma

Sample Output

2
3
4

Source

University of Waterloo Local Contest 2008.09