public void PostorderTraversal_Empty_ReturnEmpty()
{
var helper = new TreeTraversalSolution();
TreeNode root = null;
var result = helper.PostorderTraversal(root);
Assert.That(result, Is.EqualTo(new List <int> {
}));
}
public void PostorderTraversal_SingleItem_ReturnExpected()
{
var helper = new TreeTraversalSolution();
var root = new TreeNode
{
val = 1
};
var result = helper.PostorderTraversal(root);
Assert.That(result, Is.EqualTo(new List <int> {
1
}));
}
public void PostorderTraversal_NullFixed_ReturnExpected()
{
var helper = new TreeTraversalSolution();
var root = new TreeNode
{
val = 1,
left = new TreeNode
{
val = 2,
right = new TreeNode
{
val = 3,
left = new TreeNode
{
val = 4,
}
}
},
right = new TreeNode
{
val = 5,
right = new TreeNode
{
val = 6,
left = new TreeNode
{
val = 7,
},
right = new TreeNode
{
val = 8,
}
}
}
};
var result = helper.PostorderTraversal(root);
Assert.That(result, Is.EqualTo(new List <int> {
4, 3, 2, 7, 8, 6, 5, 1
}));
}
public void PostorderTraversal_WhenRightNull_ReturnExpected()
{
var helper = new TreeTraversalSolution();
var root = new TreeNode
{
val = 1,
left = new TreeNode
{
val = 2
},
right = null
};
var result = helper.PostorderTraversal(root);
Assert.That(result, Is.EqualTo(new List <int> {
2, 1
}));
}
public void PostorderTraversal_CompleteBTree_ReturnExpected()
{
var helper = new TreeTraversalSolution();
var root = new TreeNode
{
val = 1,
left = new TreeNode
{
val = 2,
},
right = new TreeNode
{
val = 3,
}
};
var result = helper.PostorderTraversal(root);
Assert.That(result, Is.EqualTo(new List <int> {
2, 3, 1
}));
}