Distinct Islands Problem Statement

Given a two-dimensional array/list consisting of integers 0s and 1s, where 1 represents land and 0 represents water, determine the number of distinct islands. A group of connected 1s (horizontally or vertically) forms an island.

Note:

Two islands are considered the same if one can be translated to overlap the other without rotation or reflection. If this condition is satisfied, they are considered identical.

Example:

Input:
 1 1 0
0 0 1
0 0 1
Output:
2
Explanation:

Here, two islands exist and they cannot be translated to overlap each other, thus they are distinct.

Example:

Input:
 1 1 0 0 0
1 1 0 0 0
0 0 0 1 1
0 0 0 1 1
Output:
1
Explanation:

These islands can be translated to overlap each other, thus they are not distinct. Only one distinct island exists.

Input:

N, M

The first two numbers are the dimensions of the array: 'N' rows and 'M' columns.

The subsequent 'N' lines provide the values for each row, with each row containing 'M' space-separated values of the array.

Output:

Total number of distinct islands.

Constraints:

  • 0 ≤ N ≤ 1000
  • 0 ≤ M ≤ 1000
  • Array elements are either 0 or 1
  • Time Limit: 1 sec
AnswerBot
4mo

Count the number of distinct islands in a 2D array of 0s and 1s.

  • Identify islands by performing depth-first search (DFS) on the grid

  • Use a set to store the shape of each island and check for duplicates

  • C...read more

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