# Tree: Level Order Traversal

### Problem Statement :

```Given a pointer to the root of a binary tree, you need to print the level order traversal of this tree. In level-order traversal, nodes are visited level by level from left to right. Complete the function levelOrder and print the values in a single line separated by a space.

For example:

1
\
2
\
5
/  \
3    6
\
4
For the above tree, the level order traversal is 1 -> 2 -> 5 -> 3 -> 6 -> 4.

Input Format

You are given a function,

void levelOrder(Node * root) {

}
Constraints

1 < = Nodes in the tree   <= 500

Output Format

Print the values in a single line separated by a space.```

### Solution :

```                            ```Solution in C :

In C ++ :

/*
struct node
{
int data;
node* left;
node* right;
}*/
int height(node * root)
{
if(!root)
return 0;
int lleft=height(root->left);
int rright=height(root->right);
if(lleft > rright)
return(lleft+1);
else
return (rright+1);
}
void level(node *root,int h){
if(!root)
return ;
if(h==1)
cout<<root->data<<" ";
level(root->left,h-1);
level(root->right,h-1);
}
void LevelOrder(node * root)
{
int n=height(root);
for(int i=1;i<=n;i++){
level(root,i);

}

}

In Java :

/*

class Node
int data;
Node left;
Node right;
*/
void LevelOrder(Node root)
{
Node last = root;
Node cur = null;
while (!q1.isEmpty() || !q2.isEmpty()) {
while (!q1.isEmpty()) {
cur = q1.poll();
if (cur.left != null) {
}
if (cur.right != null) {
}
System.out.print(cur.data + " ");
}
while (!q2.isEmpty()) {
cur = q2.poll();
if (cur.left != null) {
}
if (cur.right != null) {
}
System.out.print(cur.data + " ");
}
}
}

In python3 :

"""
Node is defined as
self.left (the left child of the node)
self.right (the right child of the node)
self.info (the value of the node)
"""
def levelOrder(root):
myQ = [root]

while(len(myQ) > 0):
iter = myQ.pop(0)
print(iter.info,end = " ")
if (iter.left != None):
myQ.append(iter.left)
if (iter.right != None):
myQ.append(iter.right)

In C :

/* you only have to complete the function given below.
node is defined as

struct node {

int data;
struct node *left;
struct node *right;

};

*/int height(struct node* root)
{
if(!root)
return 0;
else
{
int rl=height(root->left);
int rr=height(root->right);
if(rl>rr)
return rl+1;
else
return rr+1;
}
}void printlevelorder(struct node* root,int level)
{
if(!root)
return;
else if(level==1)
printf("%d ",root->data);
else if(level>1)
{
printlevelorder(root->left,level-1);
printlevelorder(root->right,level-1);
}
}
void levelOrder( struct node *root) {
int h=height(root);
int i;
for(i=0;i<=h;i++)
{
printlevelorder(root,i);
}

}```
```

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