1114 Family Property(25 分)

该程序接收每个人的房产信息及其家庭成员情况,统计每个家庭的人口数量、人均房产面积和套数,并按人均面积降序输出。

摘要生成于 C知道 ,由 DeepSeek-R1 满血版支持, 前往体验 >

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

思路:

给定每个人的家庭成员和其自己名下的房产,请你统计出每个家庭的人口数、人均房产面积及房产套数。首先在第一行输出家庭个数(所有有亲属关系的人都属于同一个家庭)。随后按下列格式输出每个家庭的信息:家庭成员的最小编号 家庭人口数 人均房产套数 人均房产面积。其中人均值要求保留小数点后3位。家庭信息首先按人均面积降序输出,若有并列,则按成员编号的升序输出。

C++:

#include <cstdio>
#include <algorithm>
using namespace std;
struct DATA {
    int id, fid, mid, num, area;
    int cid[10];
}data[1005];
struct node {
    int id, people;
    double num, area;
    bool flag = false;
}ans[10000];
int father[10000];
bool visit[10000];
int find(int x) {
    while(x != father[x])
        x = father[x];
    return x;
}
void Union(int a, int b) {
    int faA = find(a);
    int faB = find(b);
    if(faA > faB)
        father[faA] = faB;
    else if(faA < faB)
        father[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, cnt = 0;
    scanf("%d", &n);
    for(int i = 0; i < 10000; i++)
        father[i] = i;
    for(int i = 0; i < n; i++) {
        scanf("%d %d %d %d", &data[i].id, &data[i].fid, &data[i].mid, &k);
        visit[data[i].id] = true;
        if(data[i].fid != -1) {
            visit[data[i].fid] = true;
            Union(data[i].fid, data[i].id);
        }
        if(data[i].mid != -1) {
            visit[data[i].mid] = true;
            Union(data[i].mid, data[i].id);
        }
        for(int j = 0; j < k; j++) {
            scanf("%d", &data[i].cid[j]);
            visit[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 = find(data[i].id);
        ans[id].id = id;
        ans[id].num += data[i].num;
        ans[id].area += data[i].area;
        ans[id].flag = true;
    }
    for(int i = 0; i < 10000; i++) {
        if(visit[i])
            ans[find(i)].people++;
        if(ans[i].flag)
            cnt++;
    }
    for(int i = 0; i < 10000; i++) {
        if(ans[i].flag) {
            ans[i].num = (double)(ans[i].num * 1.0 / ans[i].people);
            ans[i].area = (double)(ans[i].area * 1.0 / ans[i].people);
        }
    }
    sort(ans, ans + 10000, cmp1);
    printf("%d\n", cnt);
    for(int i = 0; i < cnt; i++)
        printf("%04d %d %.3f %.3f\n", ans[i].id, ans[i].people, ans[i].num, ans[i].area);
    return 0;
}

 

<think>我们正在讨论“family of facts”概念,这通常与数学教育中的基本运算(如加法和减法,或乘法和除法)相关。一个事实族指的是一组相互关联的数学事实,这些事实使用相同的数字,但以不同的方式组合。例如,在加法和减法中,对于数字3、4和7,事实族包括: 3 + 4 = 7 4 + 3 = 7 7 - 3 = 4 7 - 4 = 3 在乘法和除法中,对于数字2、5和10,事实族包括: 2 × 5 = 10 5 × 2 = 10 10 ÷ 2 = 5 10 ÷ 5 = 2 在教育环境中,事实族被用来帮助学生理解数字之间的关系和运算的可逆性。这有助于学生发展数感和心算能力。 为了准确回答,我们需要进行网络搜索,以获取关于“family of facts”的权威定义及其在教育中的使用方式。我们将重点搜索教育网站、数学教育资源和学术定义。 搜索关键词: - "family of facts definition" - "fact families in education" - "teaching fact families" - "what are fact families in math" 通过搜索,我们可以整合信息,形成清晰、详细的回答。</think>"Family of facts" (also called *fact families*) refers to a set of related arithmetic equations derived from the same set of numbers, typically focusing on inverse operations. These groups help learners understand the relationship between addition/subtraction or multiplication/division. ### Core Concept A fact family uses three numbers to create four equations: - **Addition/Subtraction Family**: For numbers $a$, $b$, and $c$ (where $c = a + b$): $$a + b = c$$ $$b + a = c$$ $$c - a = b$$ $$c - b = a$$ *Example*: Numbers 3, 5, 8 form: $3 + 5 = 8$, $5 + 3 = 8$, $8 - 3 = 5$, $8 - 5 = 3$. - **Multiplication/Division Family**: For numbers $a$, $b$, and $c$ (where $c = a \times b$): $$a \times b = c$$ $$b \times a = c$$ $$c \div a = b$$ $$c \div b = a$$ *Example*: Numbers 2, 4, 8 form: $2 \times 4 = 8$, $4 \times 2 = 8$, $8 \div 2 = 4$, $8 \div 4 = 2$. ### Educational Applications **Foundational Skill Building** Fact families introduce inverse operations, demonstrating how addition "undoes" subtraction and multiplication "undoes" division. This builds number sense and pre-algebraic thinking. **Problem-Solving Scaffolding** Students use fact families to derive missing numbers in equations. For example, knowing $7 + \_\_ = 12$ can be solved by recalling $12 - 7 = 5$ from the same family. **Visual Tools** Teachers use diagrams like *fact family triangles* or *number bonds*: ```plaintext [8] / \ [3] [5] → Equations: 3+5=8, 5+3=8, 8-3=5, 8-5=3 ``` **Curriculum Integration** - **Early Elementary (Grades 1-2)**: Focus on addition/subtraction families within 20. - **Upper Elementary (Grades 3-4)**: Extend to multiplication/division families (e.g., 6×7=42, 42÷7=6). - **Intervention**: Used to address gaps in arithmetic fluency by reinforcing core relationships. **Cognitive Benefits** - Reduces memorization burden by grouping facts. - Reinforces commutative property (e.g., $a + b = b + a$). - Supports mental math strategies (e.g., "If 9+6=15, then 15-9 must be 6"). ### Limitations and Adaptations - **Avoid overgeneralization**: Not all number sets form valid families (e.g., 3, 3, 9 works for $3×3=9$, but 3, 4, 12 does not). - **Scaffolded practice**: Begin with concrete manipulatives (counters, blocks) before abstract equations. - **Tech integration**: Digital tools like [Mathigon](https://mathigon.org/) or [Khan Academy](https://www.khanacademy.org/) offer interactive fact family exercises.
评论
添加红包

请填写红包祝福语或标题

红包个数最小为10个

红包金额最低5元

当前余额3.43前往充值 >
需支付:10.00
成就一亿技术人!
领取后你会自动成为博主和红包主的粉丝 规则
hope_wisdom
发出的红包
实付
使用余额支付
点击重新获取
扫码支付
钱包余额 0

抵扣说明:

1.余额是钱包充值的虚拟货币,按照1:1的比例进行支付金额的抵扣。
2.余额无法直接购买下载,可以购买VIP、付费专栏及课程。

余额充值