Given a binary tree, Count leaf nodes

A leaf node is a node which doesn't have any children.

e.g. for the below tree

2
/
4 5
/
1 3

Here 1, 3 and 5 are leaf nodes.

The binary tree should be created using structure'struct node'.

Write a function:
int solution(struct node * R)

that accept root node of binary tree R of type 'struct node'.The function should return the count of a leaf nodes.

Input
5
1 3 4 5 2
1 4 3 2 5

Where,

• First line of input represents the size of an arrayN.
• Second line contains post-order arrayrepresentation.
• Third line contains in-order array representation.

Output

3

Assume that,

• Structure “struct node” is already defined.
• N is an integer within the range [1 to 10000].
• Array elements are integers within the range [-2147483648to 2147483647].

use the code below:

import java.util.*;

public class Solution {

static class Node {
int key;
Node left;
Node right;

Node(int n) {
key = n;
left = null;
right = null;
}
}

static Node createTree(int in[], int post[], intn) {
if(n <= 0) {
return null;
}
if(n == 1) {
return new Node(in[0]);
}

int rootNode =post[n-1];
Node root = newNode(rootNode);
int i;
for(i = 0; i < n;i++) {
if(in[i] == rootNode) {
break;
}
}

int leftlen = i,rightlen = n-i-1;
int leftin[] = newint[leftlen];
int rightin[] = newint[rightlen];
System.arraycopy(in,0,leftin,0,leftlen);
System.arraycopy(in,leftlen+1,rightin,0,rightlen);

int leftpost[] = newint[leftlen];
int rightpost[] = newint[rightlen];
System.arraycopy(post,0,leftpost,0,leftlen);
System.arraycopy(post,leftlen,rightpost,0,rightlen);

root.left =createTree(leftin,leftpost,leftlen);
root.right =createTree(rightin,rightpost,rightlen);
return root;
}

static int solution(Node node) {
int numOfLeafNodes =0;
// TODO: Write your codehere
returnnumOfLeafNodes;
}

public static void main(String[] args) {
Scanner sc = newScanner(System.in);
int n =sc.nextInt();
if(n == 0) {
return;
}
int in[] = newint[n];
int post[] = newint[n];
for(int i = 0; i < n;i++) {
post[i] = sc.nextInt();
}
for(int i = 0; i < n;i++) {
in[i] = sc.nextInt();
}
Node root =createTree(in,post,n);
int ans =solution(root);
System.out.println(ans);
}
}