function insert(root, value)
{
if(root === null)
return {value: value, left: null, right: null};
else if(root.value === value)
return root;
else if(value < root.value)
{
let node = insert(root.left, value);
if(root.left === null)
root.left = node;
return node;
}
else
{
let node = insert(root.right, value);
if(root.right === null)
root.right = node;
return node;
}
}