Skip to content
DSA in JavaScript

Problem patterns

Spot the signal in a problem, open the pattern, step through it, then practise.

Arrays & Strings

0/130 problems
Hash Map / Set Lookup
2
7
11
15
2→0

0/18 solved

Two Pointerscore
1
2
4
6
8
11

0/19 solved

Sliding Windowcore
a
b
c
a
d

0/18 solved

Prefix Sumcore
3
1
4
2
5
3
·
·
·
·

0/15 solved

Modified Binary Searchcore
1
3
5
7
9
11
13

0/19 solved

Sort First
2
2
5
7
9

0/13 solved

Overlapping Intervalscore

0/15 solved

String Matching
a
b
a
b
c
a
b
a
b
c

0/13 solved

Linked Lists

0/27 problems
Fast & Slow Pointerscore
1
→
2slow
→
3fast
→
4
→
5
↩ tail points to node 3

0/13 solved

In-Place Reversalcore
null←
1prev
→
2cur
→
3
→
4

0/14 solved

Stacks, Heaps & Tries

0/46 problems
Monotonic Stackcore
2
1
5
3
6
?
?
?
?
?
2
stack

0/20 solved

Top K Elementscore
5
1
9
3
7
2
1
5
9

0/16 solved

Trie / Prefix Search
·catr

0/10 solved

Trees & Graphs

0/102 problems
Binary Tree Traversalcore
791152

0/18 solved

Depth-First Searchcore
791152

0/18 solved

Breadth-First Searchcore
791152

0/18 solved

Matrix Traversalcore
00000001000111000100

0/18 solved

Topological Sort
A
B
C
D
0
1
1
2
A

0/10 solved

Union-Find
0
1
2
3
4
0
0
2
3
4

0/12 solved

Weighted Shortest Path
A
B
C
D
0
4
1
∞

0/8 solved

Recursion & Optimisation

0/76 problems
Divide & Conquer
6
3
8
2

0/12 solved

Backtrackingcore
[ ][1][ ][1,2][1][2][ ]

0/20 solved

Greedy
2
3
1
1
4

0/14 solved

Dynamic Programmingcore
0
1
2
3
4
5
1
1
·
·
·
·

0/30 solved

Math & Bits

0/29 problems
Bit Manipulation
4
1
2
1
2
0
4
·
·
·
·

0/14 solved

Number Theory
48
18
18
12

0/15 solved