List Leaves

8
1 -
- -
0 -
2 7
- -
- -
5 -
4 6

4 1 5

 1 #include <stdio.h>
 2 #include <queue>
 3 #include <algorithm>
 4 #define MaxTree 11
 5 #define Null -1 
 6 using namespace std;
 7 
 8 int check[MaxTree];
 9 int P[MaxTree];
10 int num=0;
11 queue<int> qu;
12 
13 struct TreeNode
14 {
15     int Left;
16     int Right; 
17 }T[MaxTree];
18 
19 int BuildTree(struct TreeNode T[])
20 {
21     int N,i;
22     char le,ri;
23     int Root;
24     scanf("%d\n",&N);
25     if(N)
26     {
27         for(i=0;i<N;i++)
28         {
29             check[i]=0;
30         }
31         for(i=0;i<N;i++)
32         {
33             scanf("%c %c\n",&le,&ri);
34             if(le!=‘-‘)
35             {
36                 T[i].Left=le-‘0‘;
37                 check[T[i].Left]=1;
38             }
39             else T[i].Left=Null;
40             if(ri!=‘-‘)
41             {
42                 T[i].Right=ri-‘0‘;
43                 check[T[i].Right]=1;
44             }
45             else T[i].Right=Null;
46         }
47         for(i=0;i<N;i++)
48         {
49             if(!check[i]) break;
50         }
51         Root = i;
52     }
53     else 
54     {
55         Root=Null;
56     }
57     return Root;
58 }
59 
60 void search(int Tree)
61 {
62     if(Tree!=Null)
63     {
64         qu.push(Tree);
65         while(!qu.empty())
66         {
67             int k;
68             k=qu.front();
69             if(T[k].Left==Null&&T[k].Right==Null)
70                 P[num++]=k;
71             qu.pop();;
72             if(T[k].Left!=Null)
73                 qu.push(T[k].Left);
74             if(T[k].Right!=Null)
75                 qu.push(T[k].Right);
76         }
77     }
78     else return;
79 }
80 
81 int main()
82 {
83     int Tree;
84     Tree=BuildTree(T);
85     search(Tree);
86     int i;
87     for(i=0;i<num;i++)
88     {
89         if(i==0)
90             printf("%d",P[i]);
91         else printf(" %d",P[i]);
92     }
93     return 0;
94 }