1501 二叉树最大宽度和高度 （BFS+树的遍历）

题目：http://www.wikioi.com/problem/1501/

给你一颗二叉树，求该数的宽和高，

首先求出树的高，直接进行二叉树遍历，能够得到二叉树的高

然后是得到宽，本人采用的是一层一层的遍历，求出每一层节点的个数，最大的则是该树的宽了，

代码：

  1 #include <cstdio>
  2 #include <cstring>
  3 #include <stack>
  4 #include <queue>
  5 #include <iostream>
  6 
  7 using namespace std;
  8 
  9 #define L 1
 10 #define R 2
 11 class tree{
 12 private:
 13     int a[20][3],h,w;
 14     stack<int> mystack;
 15 public:
 16     tree();
 17     void set_tree(int i,int x,int y);
 18     void tree_h(int i,int t);//得到高
 19     void BFS(int t);//得到宽
 20     int get_h();
 21     int get_w();
 22 };
 23 
 24 tree::tree()
 25 {
 26  memset(a,0,sizeof(a));
 27  h = 0;
 28  w = 0;
 29 }
 30 
 31 void tree::set_tree(int i,int x,int y)
 32 {
 33     a[i][L] = x;
 34     a[i][R] = y;
 35 }
 36  int tree::get_h()
 37  {
 38     int t = 1;
 39     tree::tree_h(a[1][L],t+1);
 40     tree::tree_h(a[1][R],t+1);
 41     return h-1;
 42  }
 43 int tree::get_w()
 44 {
 45     mystack.push(1);
 46     tree::BFS(1);
 47     return w;
 48 }
 49 void tree::BFS(int i)
 50 {
 51     if(i <= h)
 52     {
 53         int t = 0,x;
 54         stack<int> tmpstack;
 55         while(mystack.empty() == false)
 56         {
 57             x = mystack.top();
 58             mystack.pop();
 59             if(x != 0)
 60             {
 61                 t++;
 62                 tmpstack.push(a[x][L]);
 63                 tmpstack.push(a[x][R]);
 64             }
 65         }
 66 
 67         w = w > t ? w : t;
 68         mystack = tmpstack;
 69         tree::BFS(i+1);
 70     }
 71 }
 72 
 73 void tree::tree_h(int i,int t)
 74 {
 75     if(i == 0)
 76     {
 77         h = h > t ? h : t;
 78         return;
 79     }
 80     else
 81     {
 82         tree::tree_h(a[i][L],t+1);
 83         tree::tree_h(a[i][R],t+1);
 84     }
 85 }
 86 int main()
 87 {
 88     int n,x,y;
 89     while(~scanf("%d",&n))
 90     {
 91         tree mytree;
 92         for(int i = 1; i <= n; i++)
 93             {
 94                 scanf("%d%d",&x,&y);
 95                 mytree.set_tree(i,x,y);
 96             }
 97        int h = mytree.get_h();
 98        int w = mytree.get_w();
 99        printf("%d %d\n",w,h);
100     }
101     return 0;
102 }