Find duplicate rows in a binary matrix
Hard Accuracy: 69.54% Submissions: 685 Points: 8

Given a boolean matrix of size RxC where each cell contains either 0 or 1, find the row numbers of row (0-based) which already exists or are repeated.

Example 1:

Input:
R = 2, C = 2
matrix[][] = {{1, 0},
              {1, 0}}
Output: 
1
Explanation:
Row 1 is duplicate of Row 0.


Example 2:

Input:
R = 4, C = 3
matrix[][] = {{ 1, 0, 0},
              { 1, 0, 0},
              { 1, 0, 0},
              { 0, 0, 0}}
Output: 
1 2 
Explanation:
Row 1 and Row 2 are duplicates of Row 0. 


Your Task:
You dont need to read input or print anything. Complete the function repeatedRows() that takes the matrix as input parameter and returns a list of row numbers which are duplicate rows.

 

Expected Time Complexity: O(R * C)
Expected Auxiliary Space: O(R*C) 

 

Constraints:
1 ≤ R ≤ 1000
1 ≤ C ≤ 20

0 ≤ matrix[i][j] ≤ 1

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Find duplicate rows in a binary matrix

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