A supply chain is a network of retailers（零售商）, distributors（经销商）, and suppliers（供应商）-- everyone involved in moving a product from supplier to customer.
Starting from one root supplier, everyone on the chain buys products from one's supplier in a price P and sell or distribute them in a price that is r% higher than P. Only the retailers will face the customers. It is assumed that each member in the supply chain has exactly one supplier except the root supplier, and there is no supply cycle.
Now given a supply chain, you are supposed to tell the total sales from all the retailers.
Input Specification:
Each input file contains one test case. For each case, the first line contains three positive numbers: N (<=105), the total number of the members in the supply chain (and hence their ID's are numbered from 0 to N-1, and the root supplier's ID is 0); P, the unit price given by the root supplier; and r, the percentage rate of price increment for each distributor or retailer. Then N lines follow, each describes a distributor or retailer in the following format:
Ki ID[1] ID[2] ... ID[Ki]
where in the i-th line, Ki is the total number of distributors or retailers who receive products from supplier i, and is then followed by the ID's of these distributors or retailers. Kj being 0 means that the j-th member is a retailer, then instead the total amount of the product will be given after Kj. All the numbers in a line are separated by a space.
Output Specification:
For each test case, print in one line the total sales we can expect from all the retailers, accurate up to 1 decimal place. It is guaranteed that the number will not exceed 1010.
Sample Input:10 1.80 1.00 3 2 3 5 1 9 1 4 1 7 0 7 2 6 1 1 8 0 9 0 4 0 3Sample Output:
42.4
给定条件：
1.有n个节点
2.每个节点的孩子节点
3.叶子节点的权重，根节点的权重
4.其中父节点表示孩子节点的供货“上家”
5.根节点权重表示“总供应商（唯一）”的物品单价
6.叶子节点权重表示，物品数量
7.孩子节点从父节点拿货需要多付r%
要求：
1.所有零售商进货共花费多少？即叶子节点
解答：
1.遍历该树，求出叶子节点的深度
2.根据条件：深度，总供货商的物品单价，零售商物品数量，可以求出总的花费
#include<cstdio>
#include<vector>
#include<cmath>
using namespace std;int n, t, v;
int w[100001], depth[100001];
double p, r, ans;
vector<int> node[100001];void dfs(int v, int d){if(w[v] != 0){depth[v] = d;return ;}for(int i = 0; i < node[v].size(); i++){dfs(node[v][i], d+1);}
}int main(){while(scanf("%d%lf%lf", &n, &p, &r) != EOF){fill(w, w+100001, 0);fill(depth, depth+100001, 0);for(int i = 0; i < 100001; i++){node[i].clear();}for(int i = 0; i < n; i++){scanf("%d", &t);if(t != 0){for(int j = 0; j < t; j++){scanf("%d", &v);node[i].push_back(v);}}else{scanf("%d", &v);w[i] = v;}}dfs(0, 1);ans = 0;for(int i = 0; i < n; i++){if(w[i] != 0){ans = ans + (1.0)*w[i] * p * pow((100.0+r)/100.0,depth[i]-1);}}printf("%.1f\n", ans);}return 0;
}