1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21 |
```TreeNode* helper(vector<int> pre ,int startPre,int endPre,vector<int>in,int startIn,int endIn)
{
if(startPre>endPre||startIn>endIn)
return nullptr;
TreeNode * root=new TreeNode( pre [startPre]);
for(int i=startIn;i<=endIn;++i)
{
if(in[i]== pre [startPre])
{
root-> left =helper( pre ,startPre+ 1 ,startPre+i-startIn,in,startIn,i -1 );
root-> right =helper( pre ,i-startIn+startPre+ 1 ,endPre,in,i+ 1 ,endIn);
break;
}
}
return root;
}
TreeNode* reConstructBinaryTree(vector<int> pre ,vector<int> vin)
{
TreeNode *root=helper( pre , 0 , pre .size() -1 ,vin, 0 ,() -1 );
return root;
}
|