题目描述

dfs

样例

#include<iostream>
#include<cstring>
#include<queue>
#include<unordered_map>
using namespace std;
int a[200];
int memo[200];
int dfs(int i)
{
    if (i == 1)
    {
        return 1;
    }
    if (memo[i])
    {
        return memo[i];
    }
    return memo[i] = (dfs(a[i]) + 1);
}
int main()
{
    int N, M;
    cin >> N >> M;
    memset(memo, 0, sizeof memo);
    while (M--)
    {
        int parent;
        int y;
        scanf("%d %d", &parent, &y);
        while (y--)
        {
            int child;
            scanf("%d", &child);
            a[child] = parent;
        }
    }
    unordered_map<int, int> mp;
    int ans = 0;
    int c = 1;
    for (int i = 1; i <= N; i++)
    {
        int t = dfs(i);
        mp[t]++;
        if(mp[t]>=mp[c])
        {
            ans=mp[t];
            c=t;
        }
    }
    cout << ans << " " << c;
    return 0;
}