The Largest Generation

题目描述

A family hierarchy is usually presented by a pedigree tree where all the nodes on the same level belong to the same generation. Your task is to find the generation with the largest population.

输入描述:

Each input file contains one test case. Each case starts with two positive integers N (<100) which is the total number of family members in the tree (and hence assume that all the members are numbered from 01 to N), and M (<N) which is the number of family members who have children. Then M lines follow, each contains the information of a family member in the following format: ID K ID[1] ID[2] ... ID[K] where ID is a two-digit number representing a family member, K (>0) is the number of his/her children, followed by a sequence of two-digit ID's of his/her children. For the sake of simplicity, let us fix the root ID to be 01. All the numbers in a line are separated by a space.

输出描述:

For each test case, print in one line the largest population number and the level of the corresponding generation. It is assumed that such a generation is unique, and the root level is defined to be 1.

输入例子:

23 13 21 1 23 01 4 03 02 04 05 03 3 06 07 08 06 2 12 13 13 1 21 08 2 15 16 02 2 09 10 11 2 19 20 17 1 22 05 1 11 07 1 14 09 1 17 10 1 18

输出例子:

9 4

代码：

#include"iostream" #include "cstring" #include "cmath" #include "vector" #include<iomanip> using namespace std; struct Person { int Generation = 0; }; Person people[101]; vector<int> Generation[101]; void SetLength(int index, int length) { people[index].Generation = length; if (Generation[index].size() != 0) for (int i = 0; i < Generation[index].size(); i++) SetLength(Generation[index][i], length + 1); } int main() { int N, M; cin >> N >> M; for (int i = 0; i < M; i++) { int k, index; cin >> index >> k; for (int j = 0; j < k; j++) { int temp; cin >> temp; Generation[index].push_back(temp); } } SetLength(1, 1); int count[101]; memset(count, 0, sizeof(count)); for (int i = 1; i <= N; i++) { count[people[i].Generation]++; } int max = -1, index = 0; for (int i = 1; i <= N; i++) { if (count[i] > max) { max = count[i]; index = i; } } cout << max << " " << index; }

思路：

采用哈希表，哈希函数为原值。