http://www.geeksforgeeks.org/boundary-traversal-of-binary-tree/
1
#include <iostream>
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#include <vector>
3
#include <algorithm>
4
#include <queue>
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#include <stack>
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#include <
string
>
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#include <fstream>
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#include <map>
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using
namespace
std;
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struct
node {
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int
data;
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struct
node *left, *
right;
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node() : data(
0
), left(NULL), right(NULL) { }
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node(
int
d) : data(d), left(NULL), right(NULL) { }
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};
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void
printleft(node *
root) {
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if
(!root)
return
;
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if
(root->
left) {
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cout << root->data <<
"
"
;
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printleft(root->
left);
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}
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else
if
(root->
right) {
25
cout << root->data <<
"
"
;
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printleft(root->
right);
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}
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}
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void
printleaf(node *
root) {
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if
(!root)
return
;
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printleaf(root->
left);
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if
(!root->left && !root->right) cout << root->data <<
"
"
;
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printleaf(root->
right);
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}
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void
printright(node *
root) {
38
if
(!root)
return
;
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if
(root->
right) {
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printright(root->
right);
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cout << root->data <<
"
"
;
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}
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else
if
(root->
left) {
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printright(root->
left);
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cout << root->data <<
"
"
;
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}
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}
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void
printboundary(node *
root) {
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if
(!root)
return
;
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cout << root->data <<
"
"
;
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printleft(root->
left);
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printleaf(root);
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printright(root->
right);
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}
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int
main() {
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node *root =
new
node(
20
);
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root->left =
new
node(
8
);
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root->right =
new
node(
22
);
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root->left->left =
new
node(
4
);
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root->left->right =
new
node(
12
);
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root->right->right =
new
node(
25
);
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root->left->right->left =
new
node(
10
);
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root->left->right->right =
new
node(
14
);
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printboundary(root);
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return
0
;
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}
Data Structure Binary Tree: Boundary Traversal of binary tree
