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Problem · Matrix

Minimum Replacements Required to Make a Matrix Balanced

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Problem statement

You are given a matrix with exactly two rows and n columns. Every cell contains R, W, or ?.

In one replacement, choose a cell containing ? and replace it with either R or W. Question marks that are not needed may remain unchanged.

The matrix is balanced when every row and every column contains an equal number of R and W cells. Question marks are not counted. Return the minimum number of replacements required to make the matrix balanced.

Function

minimumReplacementsRequired(matrix: char[][]) → int

Examples

Example 1

matrix = [['W','R','?','?','?'],['R','?','?','?','W']]return = 4

Set the second cell of row 2 to W, the fifth cell of row 1 to R, and replace the two question marks in column 4 with W above R. The remaining ?/? column can stay unchanged. Each row then has two W and two R cells, and every column is balanced, for a total of 4 replacements.

Constraints

Standard Huge Constraints

More Microsoft problems

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public int minimumReplacementsRequired(char[][] matrix) {
  // write your code here
}
matrix[['W','R','?','?','?'],['R','?','?','?','W']]
expected4
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