Array Techniques

Question 1

Technique 1

Answer 1

Sliding window

the two pointers usually move in the same direction will never overtake

Question 2

Technique 2

Answer 2

Two pointers

two pointers is a more general version of sliding window where the point

Question 3

Technique 4

Answer 3

Sorting the array

s the array sorted or partially sorted? If it is, some form of binary se

**Sometimes sorting the array first may significantly simplify the problem. Obviously this would not work if the order of array elements need to be preserved. **

Question 3

Technique 3

Answer 3

Traversing from the right

Sometimes you can traverse the array starting from the right instead of

Question 4

Technique 5

Answer 4

Precomputation

For questions where summation or multiplication of a subarray is involve

Question 4

Technique 6

Answer 4

Index as a hash key

If you are given a sequence and the interviewer asks for O(1) space, it

Question 5

Technique 7

Answer 5

Traversing the array more than once

This might be obvious, but traversing the array twice/thrice (as long as