题目描述

C++代码

样例

#include<iostream>
#include<vector>
#include<iomanip>
using namespace std;
const int N = 1e5 + 10;
int n;
double a, b;
struct Node {
    vector<int> ne;
    bool vis;
}node[N];
double memo[N];
double dfs(int x,double d)
{

    if(memo[x]!=0)
    {
        return memo[x];
    }
    if (node[x].vis == true)
    {
        return memo[x]= (d * node[x].ne[0]);
    }
    else {
        double d1 = 0;
        for (int i = 0; i < node[x].ne.size(); i++)
        {
            double p = dfs(node[x].ne[i], (d*(1+0.01*b)));
            memo[node[x].ne[i]]=p;
            d1+=p;
        }
        return memo[x]=d1;
    }
}
int main()
{
    cin >> n >> a >> b;
    for (int i = 0; i < n; i++)
    {
        int x;
        cin >> x;
        if (x == 0)
        {
            int y;
            cin >> y;
            node[i].vis = true;
            node[i].ne.push_back(y);
        }
        else {
            node[i].vis = false;
            while (x--)
            {
                int y;
                cin >> y;
                node[i].ne.push_back(y);
            }
        }
    }
    cout << fixed << setprecision(1) << dfs(0, a);
    return 0;
}