A family hierarchy is usually presented by a pedigree tree. Your job is to count those family members who have no child.
Input Specification:
Each input file contains one test case. Each case starts with a line containing 0<N<100, the number of nodes in a tree, and M (<N), the number of non-leaf nodes. Then M lines follow, each in the format:
ID K ID[1] ID[2] ... ID[K]
where ID
is a two-digit number representing a given non-leaf node, K
is the number of its children, followed by a sequence of two-digit ID
's of its children. For the sake of simplicity, let us fix the root ID to be 01
.
The input ends with N being 0. That case must NOT be processed.
Output Specification:
For each test case, you are supposed to count those family members who have no child for every seniority level starting from the root. The numbers must be printed in a line, separated by a space, and there must be no extra space at the end of each line.
The sample case represents a tree with only 2 nodes, where 01
is the root and 02
is its only child. Hence on the root 01
level, there is 0
leaf node; and on the next level, there is 1
leaf node. Then we should output 0 1
in a line.
Sample Input:
2 1
01 1 02
Sample Output:
0 1
題意:
給出樹各個非葉節點對應的子節點,輸出各深度的葉節點數
分析:
用vector數組存各個節點的子節點,用數組存儲各深度葉節點數,DFS各個節點,DFS兩個參數分別爲當前節點編號和當前深度,若當前節點爲葉節點則作爲遞歸基返回,否則DFS其所有子節點,每次DFS順便更新樹高
代碼:
#include<cstdio>
#include<iostream>
#include<vector>
#include<algorithm>
using namespace std;
int N, M;
int leaf[100]={0}, depth=1;//每層葉節點數,樹高//按題意根爲1//0也可以//用來控制末尾空格
vector<int> G[100];
void DFS(int ID, int tmpd){//當前節點編號,當前所在深度
depth = max(tmpd,depth);//所有訪問過的節點的深度最大值即爲樹高
if(G[ID].size()==0){//如果當前節點爲葉節點//遞歸基
leaf[tmpd]++;
return;//返回給上層調用
}
for(int i=0;i<G[ID].size();i++)//檢查當前節點的每個子節點
DFS(G[ID][i],tmpd+1);
}
int main()
{
cin>>N>>M;
for(int i=0;i<M;i++){
int ID, K;
cin>>ID>>K;
for(int j=0;j<K;j++){
int tmp;
cin>>tmp;
G[ID].push_back(tmp);
}
}
DFS(1,1);
cout<<leaf[1];
for(int i=2;i<=depth;i++) cout<<' '<<leaf[i];
return 0;
}