1114 Family Property
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 Child1⋯Childk Mestate 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; Childi’s are the ID’s of his/her children; Mestate 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 AVGsets AVGarea
where ID is the smallest ID in the family; M is the total number of family members; AVGsets is the average number of sets of their real estate; and AVGarea 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
题意
给定每个人的家庭成员以及他/她自己名字下的不动产（地产）信息，我们需要知道每个家庭的成员数，以及人均不动产面积和人均房产套数。
输入拥有房产的人员的信息，格式如下：
ID Father Mother k Child_1 ... child_k M_estate Area
输出一个家庭的相关房产信息，格式如下：
ID M AVG_sets AVG_area
按人均房产面积降序顺序输出所有家庭信息。当存在人均房产面积相同的情况时，按 ID 升序顺序排序。
思路
具体思路如下：
1.用一个结构体数组 e 来存储所有关系，并用一个结构体 family 来存储每个家庭的相关信息，然后输入拥有房产的人员信息。
2.初始化并查集，然后开始从头往后遍历每个成员关系，并更新并查集，划分出每个人员所属的家庭集合。
3.统计存在的集合个数即家庭个数，放入答案数组 res 中。
4.对答案数组进性排序，按人均房产面积降序顺序输出所有家庭信息。当存在人均房产面积相同的情况时，按 ID 升序顺序排序。
5.输出结果，注意输出房产总面积以及人均房产面积时保留 3 位小数。
代码
#include<bits/stdc++.h> using namespace std; const int N = 10010; int n, cnt; int p[N], c[N], hc[N], ha[N]; bool st[N]; struct edge { int a, b; }e[N]; struct family { int id, c, hc, ha; //重载比较运算 bool operator < (const family& f)const { // ha / c 是否等于 f.ha / f.c if (ha * f.c != f.ha * c) return ha * f.c > f.ha * c; return id < f.id; } }; //并查集模板 int find(int x) { if (p[x] != x) p[x] = find(p[x]); return p[x]; } int main() { cin >> n; //输入每个家庭信息 cnt = 0; for (int i = 0; i < n; i++) { int id, father, mother, k; cin >> id >> father >> mother >> k; st[id] = true; //判断是否有父母 if (father != -1) e[cnt++] = { id,father }; if (mother != -1) e[cnt++] = { id,mother }; //输入孩子信息 while (k--) { int x; cin >> x; e[cnt++] = { id,x }; } cin >> hc[id] >> ha[id]; } for (int i = 0; i < N; i++) p[i] = i, c[i] = 1; //初始化并查集 for (int i = 0; i < cnt; i++) //合并家庭 { int a = e[i].a, b = e[i].b; st[a] = true, st[b] = true; int pa = find(a), pb = find(b); if (pa != pb) { if (pa > pb) swap(pa, pb); c[pa] += c[pb]; hc[pa] += hc[pb]; ha[pa] += ha[pb]; p[pb] = pa; } } //统计答案 vector<family> res; for (int i = 0; i < N; i++) if (st[i] && p[i] == i) res.push_back({ i,c[i],hc[i],ha[i] }); //对答案进行排序 sort(res.begin(), res.end()); cout << res.size() << endl; for (auto& f : res) printf("%04d %d %.3lf %.3lf\n", f.id, f.c, (double)f.hc / f.c, (double)f.ha / f.c); return 0; }
