C :

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#define maxn 50010

struct node{
char name[10];
}A[maxn];

int n;
int f[maxn];

int hash_val(char str[]){
int i;
for(i = 1;i <= n; i++){
    if(strcmp(str,A[i].name)==0)return i;
}
return 0;
}

int find(int v){
if(f[v]==v)return v;
int F = find(f[v]);
f[v] = F;
return F;
}

int main()
{
    n = 0;
    char temp[10];
    int last;
    for(int i = 1;i <= 50001; i++){
        f[i] = i;
    }
    while(scanf("%s",temp) && strcmp(temp,"$") != 0){
        char str[10];
        strcpy(str,&temp[1]);
        int index = hash_val(str);
        if(temp[0]=='#'){
            if(!index){
               strcpy(A[++n].name,str);
               last = n;
            }
            else{
                last = index;
            }
        }
        if(temp[0]=='+'){
            int now;
            if(!index){
               strcpy(A[++n].name,str);
               now = n;
            }
            else{
                now = index;
            }
            int fa = find(last);
            int fb = find(now);
            f[fb] = fa;
        }
        if(temp[0]=='?'){
            int v = hash_val(str);
            int fv = find(v);
            printf("%s %s\n",str,A[fv].name);
        }
    }
    return 0;
}

C++ :

#include <iostream>
#include <cstring>
#include <cstdio>

using namespace std;

#define NMAX 50002

struct tagPerson
{
	char m_name[7];
	int m_father;
} Person[NMAX];

int g_nPeople = 0;

void InitData();
int FindAncestor(const char szName[]);
int AddPerson(const char szName[]);
int CheckPerson(const char szName[]);

int main()
{
	InitData();
	return 0;
}

void InitData()
{
	char szName[8] = "\0";
	int nFather = 0;
	char chFlag = '\0';

	cin >>szName;
	chFlag = szName[0];
	while (chFlag != '$')
	{
		if (chFlag == '#')
		{
			nFather = FindAncestor(szName + 1);
			cin >>szName;
			chFlag = szName[0];
			while (chFlag == '+')
			{
				int father = CheckPerson(szName + 1);
				if (father == -1)
				{
					father = AddPerson(szName + 1);
				}

				Person[father].m_father = nFather;

				cin >>szName;
				chFlag = szName[0];
			}
		}
		
		if (chFlag == '?')
		{
			nFather = FindAncestor(szName + 1);
			cout <<szName+1 <<' ' <<Person[nFather].m_name <<endl;
			
			cin >>szName;
			chFlag = szName[0];
		}
	}
}

int FindAncestor(const char szName[])
{
	int nFather = CheckPerson(szName);

	if (nFather == -1)
	{
		nFather = AddPerson(szName);
	}
	else
	{
		while (Person[nFather].m_father != nFather)
		{
			nFather = Person[nFather].m_father;
		}
	}
	
	return nFather;
}

int AddPerson(const char szName[])
{
	Person[g_nPeople].m_father = g_nPeople;
	strcpy(Person[g_nPeople].m_name, szName);
	++g_nPeople;
	
	return g_nPeople - 1;
}

int CheckPerson(const char szName[])
{
	for (int i = 0; i < g_nPeople; ++i)
	{
		if (strcmp(szName, Person[i].m_name) == 0)
		{
			return i;
		}
	}
	return -1;
}