Poj1470 Closest Common Ancestors LCA

#include<iostream>
#include<cstdio>
#include<cstring>
#include<map>
#include<vector>
using namespace std;
const int maxn = 1111;
int head[maxn];
int len;
struct Node
{
int to; int next;
}e[maxn * 2];
int father[maxn];
int color[maxn];
int vis[maxn];
int gg[maxn];
vector <int> q[maxn];
void add(int from, int to)
{
e[len].to = to;
e[len].next = head[from];
head[from] = len++;
}

int getfather(int x)
{
if (father[x] != x) father[x] = getfather(father[x]);
return father[x];
}

void un(int a, int b)
{
int fa = getfather(a); int fb = getfather(b);
father[fb] = fa;
}

void dfs(int x)
{
for (int i = head[x]; ~i; i = e[i].next){
int cc = e[i].to;
dfs(cc);
un(x, cc);
}
color[x] = 1;
for (int i = 0; i <q[x].size(); i++){
int t = q[x][i];
if (color[t]){
int t1 = getfather(q[x][i]);
vis[t1]++;
}
}
}

void init(int n)
{
len = 0;
memset(head, -1, sizeof(head));
for (int i = 1; i <= n; i++)
father[i] = i;
memset(head, -1, sizeof(head));
for (int i = 1; i <= n; i++)
q[i].clear();
memset(color, 0, sizeof(color));
for (int i = 1; i <= n; i++)
vis[i] = 0;
for (int i = 1; i <= n; i++)
gg[i] = 0;
}

int main()
{
int n;
while (cin >> n){
init(n);
int m, a, b, c;
for (int i = 0; i<n; i++){
scanf("%d", &a);
scanf(":(%d)", &b);
for (int j = 0; j<b; j++){
scanf("%d", &c);
add(a, c);
gg[c] = 1;
}
}
scanf("%d", &m);
while (m--){
scanf(" (%d %d)", &a, &b);
//  printf("%d %djiji\n",a,b);
q[a].push_back(b);
q[b].push_back(a);
}
int root;
for (int i = 1; i <= n; i++) if (!gg[i]){
root = i; break;
}
dfs(root);
for (int i = 1; i <= n; i++){
if (vis[i]){
printf("%d:%d\n", i, vis[i]);
}
}
}
return 0;
}