HDU 1710-binary tree traversals

The data structure of this semester is not very good. Spoof ing...

 

Tell the first and middle sequence of the Binary Tree, and find the latter sequence.

Idea: first establish a binary linked list and then traverse the binary tree.

 

# Include <cstdio> <br/> using namespace STD; <br/> typedef struct binary <br/>{< br/> int data; <br/> binary * lchild, * rchild; <br/> binary () <br/>{< br/> lchild = NULL; <br/> rchild = NULL; <br/>}< br/>} * bittree; <br/> int pre [1010], in [1010]; <br/> void build (bittree & root, int Len, int PST, int Ped, int inst, int INED) // first order creation <br/> {<br/> int I, l_len = 0; <br/> If (LEN <= 0) <br/> return; <br/> r OOT = new binary; <br/> root-> DATA = pre [PST]; <br/> for (I = inst; I <= ined; I ++) <br/> {<br/> If (in [I] = pre [PST]) <br/> {<br/> l_len = I-Inst; <br/> break; <br/>}< br/> build (root-> lchild, l_len, Pst + 1, Pst + l_len, inst, i-1); <br/> build (root-> rchild, len-1-l_len, Pst + l_len + 1, Ped, I + 1, INED ); <br/>}< br/> void travel (Binary * root) // post-order traversal <br/> {<br/> int I; <br/> If (Root) <br/> {<Br/> travel (root-> lchild); <br/> travel (root-> rchild); <br/> printf ("% d ", root-> data); <br/>}< br/> int main () <br/>{< br/> int I, N; <br/> bittree root; </P> <p> while (scanf ("% d", & N )! = EOF) <br/>{< br/> for (I = 0; I <n; I ++) <br/>{< br/> scanf ("% d", & Pre [I]); <br/>}< br/> for (I = 0; I <n; I ++) <br/>{< br/> scanf ("% d", & in [I]); <br/>}< br/> build (root, N, 0, n-1, 0, n-1); <br/> travel (root-> lchild ); <br/> travel (root-> rchild); <br/> printf ("% d/N", root-> data ); <br/>}< br/> return 0; <br/>}