PTA Family Property (25分)

释放无限光明的是人心，制造无边黑暗的也是人心，光明和黑暗交织着，厮杀着，这就是我们为之眷恋又万般无奈的人世间。

This time, you are supposed to help us collect the data for family-owned property. Given each person's family members, and the estate（房产）info under his/her own name, we need to know the size of each family, and the average area and number of sets of their real estate.

Input Specification:

Each input file contains one test case. For each case, the first line gives a positive integer N (≤1000). Then N lines follow, each gives the infomation of a person who owns estate in the format:

ID Father Mother k Child​1​​⋯Child​k​​ M​estate​​ Area

where ID is a unique 4-digit identification number for each person; Father and Mother are the ID's of this person's parents (if a parent has passed away, -1 will be given instead); k (0≤k≤5) is the number of children of this person; Child​i​​'s are the ID's of his/her children; M​estate​​ is the total number of sets of the real estate under his/her name; and Area is the total area of his/her estate.

Output Specification:

For each case, first print in a line the number of families (all the people that are related directly or indirectly are considered in the same family). Then output the family info in the format:

ID M AVG​sets​​ AVG​area​​

where ID is the smallest ID in the family; M is the total number of family members; AVG​sets​​ is the average number of sets of their real estate; and AVG​area​​ is the average area. The average numbers must be accurate up to 3 decimal places. The families must be given in descending order of their average areas, and in ascending order of the ID's if there is a tie.

Sample Input:

10
6666 5551 5552 1 7777 1 100
1234 5678 9012 1 0002 2 300
8888 -1 -1 0 1 1000
2468 0001 0004 1 2222 1 500
7777 6666 -1 0 2 300
3721 -1 -1 1 2333 2 150
9012 -1 -1 3 1236 1235 1234 1 100
1235 5678 9012 0 1 50
2222 1236 2468 2 6661 6662 1 300
2333 -1 3721 3 6661 6662 6663 1 100

Sample Output:

3
8888 1 1.000 1000.000
0001 15 0.600 100.000
5551 4 0.750 100.000

#include <iostream>
#include <cstdio>
#include <algorithm>
#include <string>
#include <cstring>
#include <cstdlib>
#include <cmath>
#include <stack>
#include <queue>
#include <set>
#include <map>
#include <vector>
#include <ctime>
#include <cctype>
#include <bitset>
#include <utility>
#include <sstream>
#include <complex>
#include <iomanip>
#include<climits>//INT_MAX
//#include<bits/stdc++.h>
#define PP pair<ll,int>
#define inf 0x3f3f3f3f
#define llinf 0x3f3f3f3f3f3f3f3fll
#define dinf 1000000000000.0
#define PI 3.1415926
typedef long long ll;
using namespace std;
int const mod=1e9+7;
const int maxn=10010;
struct DATA{
    int id, fid, mid, num, area;
    int cid[10];
}data[1010];
struct node {
    int id, pp;
    double num, area;
    bool fg=false;
}P[maxn];
int fa[maxn];
bool vis[maxn];
int fd(int x) {
    while(x!=fa[x])
        x=fa[x];
    return x;
}
void Union(int a, int b) {
    int faA=fd(a);
    int faB=fd(b);
    if(faA>faB)
        fa[faA]=faB;
    else if(faA<faB)
        fa[faB]=faA;
}
int cmp1(node a, node b) {
    if(a.area!=b.area)
        return a.area>b.area;
    else
        return a.id<b.id;
}
int main() {
    int n, k, ct=0;
    scanf("%d", &n);
    for(int i=0; i<maxn; i++)
        fa[i]=i;
    for(int i=0; i<n; i++) {
        scanf("%d %d %d %d", &data[i].id, &data[i].fid, &data[i].mid, &k);
        vis[data[i].id]=true;
        if(data[i].fid!=-1) {
            vis[data[i].fid]=true;
            Union(data[i].fid, data[i].id);
        }
        if(data[i].mid!=-1){
            vis[data[i].mid]=true;
            Union(data[i].mid, data[i].id);
        }
        for(int j=0; j<k; j++) {
            scanf("%d", &data[i].cid[j]);
            vis[data[i].cid[j]]=true;
            Union(data[i].cid[j], data[i].id);
        }
        scanf("%d %d", &data[i].num, &data[i].area);
    }
    for(int i=0; i<n; i++) {
        int id=fd(data[i].id);
        P[id].id=id;
        P[id].num+=data[i].num;
        P[id].area+=data[i].area;
        P[id].fg=true;
    }
    for(int i=0; i<maxn; i++) {
        if(vis[i])
            P[fd(i)].pp++;
        if(P[i].fg)
            ct++;
    }
    for(int i=0; i<maxn; i++) {
        if(P[i].fg){
            P[i].num=(double)(P[i].num*1.0/P[i].pp);
            P[i].area=(double)(P[i].area*1.0/P[i].pp);
        }
    }
    sort(P, P+maxn, cmp1);
    printf("%d\n", ct);
    for(int i=0; i<ct; i++)
        printf("%04d %d %.3f %.3f\n", P[i].id, P[i].pp, P[i].num, P[i].area);
    return 0;
}