Data Structure & Algorithms
DSA
Hasing
Distinct Numbers in Window

# Distinct Numbers in Window

## Problem Description

You are given an array of N integers, A1, A2 ,..., AN and an integer B. Return the of count of distinct numbers in all windows of size B.

Formally, return an array of size N-B+1 where i'th element in this array contains number of distinct elements in sequence Ai, Ai+1 ,..., Ai+B-1.

NOTE: if B > N, return an empty array.

### Problem Constraints

``````1 <= N <= 10^6
1 <= A[i] <= 10^9``````

### Input Format

``````First argument is an integer array A
Second argument is an integer B.``````

### Output Format

``Return an integer array.``

### Example Input

``````Input 1:
A = [1, 2, 1, 3, 4, 3]
B = 3

Input 2:
A = [1, 1, 2, 2]
B = 1``````

### Example Output

``````Output 1:
[2, 3, 3, 2]

Output 2:
[1, 1, 1, 1]``````

### Example Explanation

``````Explanation 1:
A=[1, 2, 1, 3, 4, 3] and B = 3
All windows of size B are
[1, 2, 1]
[2, 1, 3]
[1, 3, 4]
[3, 4, 3]
So, we return an array [2, 3, 3, 2].

Explanation 2:
Window size is 1, so the output array is [1, 1, 1, 1].``````

### Output

Java
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Python
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JavaScript
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