PAT (Advanced Level) 1090. Highest Price in Supply Chain (25)

简单dfs。

#include<cstdio>
#include<cstring>
#include<cmath>
#include<algorithm>
#include<map>
#include<queue>
#include<stack>
#include<vector>
using namespace std;

const int maxn=100000+10;
vector<int>g[maxn];
int n;
double p,r;
int root;
int ans_x;
double ans_price=0;

void dfs(int x,double price)
{
    if(g[x].size()==0)
    {
        if(price>ans_price)
        {
            ans_price=price;
            ans_x=1;
        }
        else if(price==ans_price)
        {
            ans_x++;
        }
        return;
    }

    for(int i=0;i<g[x].size();i++)
    {
        dfs(g[x][i],price*(1.0+r/100));
    }
}

int main()
{
    scanf("%d",&n);
    scanf("%lf%lf",&p,&r);

    for(int i=0;i<n;i++)
    {
        int fa; scanf("%d",&fa);
        if(fa==-1) root=i;
        else g[fa].push_back(i);
    }

    dfs(root,p);

    printf("%.2lf %d\n",ans_price,ans_x);

    return 0;
}