A1094. The Largest Generation

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.

Input Specification:

Each input file contains one test case. Each case starts with two positive integers N (&lt100) 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 (&ltN) 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 (&gt0) 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.

Output Specification:

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.

Sample Input:

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

Sample Output:

9 4

#include<iostream>
#include<cstdio>
#include<vector>
using namespace std;
typedef struct{
    int data;
    vector<int>child;
}node;
node tree[20000];
int N, M, width[20000] = {0}, maxDepth = -1;
void DFS(int s, int dp){
    if(s > N)
        return;
    width[dp]++;
    if(dp > maxDepth){
        maxDepth = dp;
    }
    for(int i = 0; i < tree[s].child.size(); i++){
        DFS(tree[s].child[i], dp + 1);
    }
}
int main(){
    scanf("%d%d", &N, &M);
    for(int i = 0; i < M; i++){
        int id, K, temp;
        scanf("%d%d", &id, &K);
        tree[id].data = id;
        for(int j = 0; j < K; j++){
            scanf("%d", &temp);
            tree[id].child.push_back(temp);
        }
    }
    DFS(1,1);
    int index = -1, max = -1;
    for(int i = 1; i <= maxDepth; i++){
        if(width[i] > max){
            max = width[i];
            index = i;
        }
    }
    printf("%d %d", max, index);
    cin >> N;
    return 0;
}