Complete vs full vs perfect binary trees in Data Structures Theory - Interactive Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the sentence: A full binary tree is a tree where every node has either {{BLANK_1}} or zero children.

Data Structures Theory

A full binary tree is a tree where every node has either [1] or zero children.

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Aone

Btwo

Cthree

Dfour

Attempts:

3 left

💡 Hint

Common Mistakes

Thinking a full binary tree can have nodes with only one child.

Confusing full binary tree with complete binary tree.

A full binary tree means each node has exactly two children or none at all.

2fill in blank

medium

Complete the sentence: A complete binary tree is a tree where all levels are fully filled except possibly the {{BLANK_1}} level, which is filled from left to right.

Data Structures Theory

A complete binary tree is a tree where all levels are fully filled except possibly the [1] level, which is filled from left to right.

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Asecond

Bfirst

Cmiddle

Dlast

Attempts:

3 left

💡 Hint

Common Mistakes

Choosing the first or middle level instead of the last level.

Confusing complete binary tree with full binary tree.

In a complete binary tree, all levels except possibly the last are fully filled, and the last level is filled from left to right.

3fill in blank

hard

Fix the error in the sentence: A perfect binary tree is a tree where all internal nodes have two children and all leaves are at {{BLANK_1}} level.

Data Structures Theory

A perfect binary tree is a tree where all internal nodes have two children and all leaves are at [1] level.

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Athe same

Bvarious

Cdifferent

Drandom

Attempts:

3 left

💡 Hint

Common Mistakes

Thinking leaves can be at different levels in a perfect binary tree.

Confusing perfect binary tree with complete binary tree.

In a perfect binary tree, all leaves are at the same level, making the tree completely balanced.

4fill in blank

hard

Fill both blanks to complete the definition: A {{BLANK_1}} binary tree is always a {{BLANK_2}} binary tree, but not all {{BLANK_2}} binary trees are {{BLANK_1}}.

Data Structures Theory

A [1] binary tree is always a [2] binary tree, but not all [2] binary trees are [1].

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Aperfect

Bcomplete

Cfull

Dbalanced

Attempts:

3 left

💡 Hint

Common Mistakes

Mixing up full and complete trees in this relationship.

Assuming all complete trees are perfect.

A perfect binary tree is always full because all internal nodes have two children and all leaves are at the same level. However, a full binary tree does not have to be perfect.

5fill in blank

hard

Fill all four blanks to complete the statement: In a {{BLANK_1}} binary tree, nodes are filled level by level from left to right; in a {{BLANK_2}} binary tree, every node has {{BLANK_3}} or zero children; and in a {{BLANK_4}} binary tree, all leaves are at the same level.

Data Structures Theory

In a [1] binary tree, nodes are filled level by level from left to right; in a [2] binary tree, every node has [3] or zero children; and in a [4] binary tree, all leaves are at the same level.

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Acomplete

Bfull

Ctwo

Dperfect

Attempts:

3 left

💡 Hint

Common Mistakes

Confusing which tree type fills nodes level by level.

Mixing the number of children nodes have in full trees.

A complete binary tree fills nodes level by level from left to right. A full binary tree has nodes with either two or zero children. A perfect binary tree has all leaves at the same level.