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Check Completeness of a Binary Tree
Bookmark
Null Flag
Node Indexing
Input
Incomplete (false)
Complete (true)
Gap at Level 2 (false)
Partial Last Level (true)
Custom
tree
=
[1, 2, 3, 4, 5, null, 7]
∅
1
2
3
4
5
7
L0
L1
L2
seenNull = false
queue
a complete tree fills each level left to right
∅
1
2
3
4
5
7
L0
L1
L2
seenNull = false
queue
a complete tree fills each level left to right
∅
1
2
3
4
5
7
L0
L1
L2
seenNull = false
queue
visit node
1
∅
1
2
3
4
5
7
L0
L1
L2
seenNull = false
queue
3
front
visit node
2
∅
1
2
3
4
5
7
L0
L1
L2
seenNull = false
queue
3
4
5
front
enqueue right:
5
∅
1
2
3
4
5
7
L0
L1
L2
seenNull = false
queue
4
5
null
front
enqueue left:
null
∅
1
2
3
4
5
7
L0
L1
L2
seenNull = false
queue
5
null
7
null
front
enqueue left:
null
∅
1
2
3
4
5
7
L0
L1
L2
seenNull = false
queue
null
7
null
null
front
visit node
5
∅
1
2
3
4
5
7
L0
L1
L2
seenNull = false
queue
null
7
null
null
null
null
front
enqueue right:
null
∅
1
2
3
4
5
7
L0
L1
L2
seenNull = true
queue
null
null
null
null
front
visit node
7
∅
1
2
3
4
5
7
L0
L1
L2
seenNull = true
queue
return false
algo
master
.
io
Step:
Start: check if the binary tree is complete
0 / 21
Input
Incomplete (false)
Complete (true)
Gap at Level 2 (false)
Partial Last Level (true)
Custom
tree
=
[1, 2, 3, 4, 5, null, 7]
0 / 21
algo
master
.
io
Step:
Start: check if the binary tree is complete
