Run error while executing

#1

why am i getting run error here? it is working fine on netbeans.

import java.util.*;
public class Generic_tree {
private class Node
{
int data;
ArrayList children;
Node(int data)
{
this.data=data;
this.children=new ArrayList<>();
}
}
private Node root=null;
private int size=0;

public Generic_tree() {
    Scanner s=new Scanner(System.in);
    this.root=takeinput(s,null,0);
}
private Node takeinput(Scanner s,Node parent,int ith_child)
{
    int nodedata=s.nextInt();
    Node node=new Node(nodedata);
    this.size++;
    
    int children=s.nextInt();
    for(int i=0;i<children;i++){
        Node child=this.takeinput(s, node, i);
        node.children.add(child);
    }
    return node;
}
public void display()
{
    this.display(this.root);
}
private void display(Node node)
{
    String str=node.data+"=>";
    for(int i=0;i<node.children.size();i++)
    {
        str= str+ node.children.get(i).data+",";
    }
    str=str+"end";
    System.out.println(str);
    
    for(int i=0;i<node.children.size();i++)
    {
        this.display(node.children.get(i));
    }
}

public int kth_sum(int k)
{
    return this.kth_sum(this.root,k);
}
private int kth_sum(Node node,int k)
{
    if(k<0)
        return -1;
        
    if(k==0)
        return node.data;
    
    int sum=0;
    for(int i=0;i<node.children.size();i++)
    {
        sum=sum+kth_sum(node.children.get(i), k-1);
    }
    return sum;
}
// 1 2 2 2 3 0 4 0 5 2 6 0 7 0 2
public static void main(String[] args) {
    Generic_tree tree=new Generic_tree();
  
    Scanner sc=new Scanner(System.in);
    int k=sc.nextInt();
    System.out.println(tree.kth_sum(k));
}

}

this is the code .

#2

can you please describe the run time error?
what is name of the error?
thanks

#3

Compile Message
run-error

#4

import java.util.*;
class Node
{
int data;
ArrayList children;
Node(int data)
{
this.data=data;
this.children=new ArrayList();
}
}
public class Generic_tree {
private Node root=null;
private int size=0;
public Generic_tree(Scanner s) {

this.root=takeinput(s);

}
private Node takeinput(Scanner s)
{
int nodedata=s.nextInt();
Node node=new Node(nodedata);
this.size++;

int children=s.nextInt();
for(int i=0;i<children;i++){
    Node child=this.takeinput(s);
    node.children.add(child);
}
return node;

}
public void display()
{
this.display(this.root);
}
private void display(Node node)
{
String str=node.data+"=>";
for(int i=0;i<node.children.size();i++)
{
str= str+ node.children.get(i).data+",";
}
str=str+“end”;
System.out.println(str);

for(int i=0;i<node.children.size();i++)
{
    this.display(node.children.get(i));
}

}

public int kth_sum(int k)
{
return this.kth_sum(this.root,k);
}
private int kth_sum(Node node,int k)
{
if(k<0)
return -1;

if(k==0)
    return node.data;

int sum=0;
for(int i=0;i<node.children.size();i++)
{
    sum=sum+kth_sum(node.children.get(i), k-1);
}
return sum;

}
// 1 2 2 2 3 0 4 0 5 2 6 0 7 0 2
public static void main(String[] args) {
Scanner s=new Scanner(System.in);
Generic_tree tree=new Generic_tree(s);

// Scanner sc=new Scanner(System.in);
int k=s.nextInt();
System.out.println(tree.kth_sum(k));
tree.display();

}}

I fixed the code. please have a look. there are some minor changes.
thanks

#5

you made changes in takeinput function.it is still showing run error in code editor. working fine in netbeans

#6

i made other changes as well like getting the class Node out. please try to paste my code in editor and let me know if it works.
thanks

#7

Still not working
Same run error

#8

wherever you are creating ArrayList, please make sure that it is of type int…
like ArrayList$Node$ children = new ArrayList$Node$();

replace $ by angular brackets…
I modified this in my earlier code but it did not show up due to problem with angular brackets.
please check it again.
thanks

#9

I checked this code https://ide.codingblocks.com/s/209041 for various test cases and its perfectly fine. there is some platform issue on hackerblocks. i tried submitting it, but its not responding anything. it happens sometimes due to some technical glitch.

thanks

#10

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