Package g1301_1400.s1337_the_k_weakest_rows_in_a_matrix

Class Solution

java.lang.Object
g1301_1400.s1337_the_k_weakest_rows_in_a_matrix.Solution
public class Solution extends java.lang.Object
1337 - The K Weakest Rows in a Matrix.

Easy

You are given an m x n binary matrix mat of 1’s (representing soldiers) and 0’s (representing civilians). The soldiers are positioned in front of the civilians. That is, all the 1’s will appear to the left of all the 0’s in each row.

A row i is weaker than a row j if one of the following is true:

  • The number of soldiers in row i is less than the number of soldiers in row j.
  • Both rows have the same number of soldiers and i < j.

Return the indices of the k weakest rows in the matrix ordered from weakest to strongest.

Example 1:

Input: mat =

[[1,1,0,0,0],

[1,1,1,1,0],

[1,0,0,0,0],

[1,1,0,0,0],

[1,1,1,1,1]], k = 3

Output: [2,0,3]

Explanation: The number of soldiers in each row is:

  • Row 0: 2
  • Row 1: 4
  • Row 2: 1
  • Row 3: 2
  • Row 4: 5

The rows ordered from weakest to strongest are [2,0,3,1,4].

Example 2:

Input: mat = [[1,0,0,0], [1,1,1,1], [1,0,0,0], [1,0,0,0]], k = 2

Output: [0,2]

Explanation: The number of soldiers in each row is:

  • Row 0: 1
  • Row 1: 4
  • Row 2: 1
  • Row 3: 1

The rows ordered from weakest to strongest are [0,2,3,1].

Constraints:

  • m == mat.length
  • n == mat[i].length
  • 2 <= n, m <= 100
  • 1 <= k <= m
  • matrix[i][j] is either 0 or 1.

  • Constructor Summary

    Constructors
    Constructor
    Description
    Solution()
     

  • Method Summary

    Modifier and Type
    Method
    Description
    int[]
    kWeakestRows(int[][] mat, int k)
     

    Methods inherited from class java.lang.Object

    clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

  • Constructor Details

    • Solution

      public Solution()

  • Method Details

    • kWeakestRows

      public int[] kWeakestRows(int[][] mat, int k)