Set Matrix Zeroes Leetcode Solution

In this post, you will know how to solve the Set Matrix Zeroes Leetcode Solution problem of Leetcode. This Leetcode problem is done in many programming languages like C++, Java, and Python.

Set Matrix Zeroes Leetcode Solution
Set Matrix Zeroes Leetcode Solutions

One more thing to add, don’t directly look for the solutions, first try to solve the problems of Leetcode by yourself. If you find any difficulty after trying several times, then you can look for solutions.

Problem

Given an m x n integer matrix matrix, if an element is 0, set its entire row and column to 0‘s.

You must do it in place.

Example 1:

Input: matrix = [[1,1,1],[1,0,1],[1,1,1]]
Output: [[1,0,1],[0,0,0],[1,0,1]]

Example 2:

Input: matrix = [[0,1,2,0],[3,4,5,2],[1,3,1,5]]
Output: [[0,0,0,0],[0,4,5,0],[0,3,1,0]]

Constraints:

  • m == matrix.length
  • n == matrix[0].length
  • 1 <= m, n <= 200
  • -231 <= matrix[i][j] <= 231 - 1

Follow up:

  • A straightforward solution using O(mn) space is probably a bad idea.
  • A simple improvement uses O(m + n) space, but still not the best solution.
  • Could you devise a constant space solution?

Set Matrix Zeroes Leetcode Solutions in Python

class Solution:
  def setZeroes(self, matrix: List[List[int]]) -> None:
    m = len(matrix)
    n = len(matrix[0])
    shouldFillFirstRow = 0 in matrix[0]
    shouldFillFirstCol = 0 in list(zip(*matrix))[0]
    # Store the information in the 1st row/col
    for i in range(1, m):
      for j in range(1, n):
        if matrix[i][j] == 0:
          matrix[i][0] = 0
          matrix[0][j] = 0
    # Fill 0s for the matrix except the 1st row/col
    for i in range(1, m):
      for j in range(1, n):
        if matrix[i][0] == 0 or matrix[0][j] == 0:
          matrix[i][j] = 0
    # Fill 0s for the 1st row if needed
    if shouldFillFirstRow:
      matrix[0] = [0] * n
    # Fill 0s for the 1st col if needed
    if shouldFillFirstCol:
      for row in matrix:
        row[0] = 0

Set Matrix Zeroes Leetcode Solutions in CPP

class Solution {
 public:
  void setZeroes(vector<vector<int>>& matrix) {
    const int m = matrix.size();
    const int n = matrix[0].size();
    bool shouldFillFirstRow = false;
    bool shouldFillFirstCol = false;
    for (int j = 0; j < n; ++j)
      if (matrix[0][j] == 0) {
        shouldFillFirstRow = true;
        break;
      }
    for (int i = 0; i < m; ++i)
      if (matrix[i][0] == 0) {
        shouldFillFirstCol = true;
        break;
      }
    // Store the information in the 1st row/col
    for (int i = 1; i < m; ++i)
      for (int j = 1; j < n; ++j)
        if (matrix[i][j] == 0) {
          matrix[i][0] = 0;
          matrix[0][j] = 0;
        }
    // Fill 0s for the matrix except the 1st row/col
    for (int i = 1; i < m; ++i)
      for (int j = 1; j < n; ++j)
        if (matrix[i][0] == 0 || matrix[0][j] == 0)
          matrix[i][j] = 0;
    // Fill 0s for the 1st row if needed
    if (shouldFillFirstRow)
      for (int j = 0; j < n; ++j)
        matrix[0][j] = 0;
    // Fill 0s for the 1st col if needed
    if (shouldFillFirstCol)
      for (int i = 0; i < m; ++i)
        matrix[i][0] = 0;
  }
};

Set Matrix Zeroes Leetcode Solutions in Java

class Solution {
  public void setZeroes(int[][] matrix) {
    final int m = matrix.length;
    final int n = matrix[0].length;
    boolean shouldFillFirstRow = false;
    boolean shouldFillFirstCol = false;
    for (int j = 0; j < n; ++j)
      if (matrix[0][j] == 0) {
        shouldFillFirstRow = true;
        break;
      }
    for (int i = 0; i < m; ++i)
      if (matrix[i][0] == 0) {
        shouldFillFirstCol = true;
        break;
      }
    // Store the information in the 1st row/col
    for (int i = 1; i < m; ++i)
      for (int j = 1; j < n; ++j)
        if (matrix[i][j] == 0) {
          matrix[i][0] = 0;
          matrix[0][j] = 0;
        }
    // Fill 0s for the matrix except the 1st row/col
    for (int i = 1; i < m; ++i)
      for (int j = 1; j < n; ++j)
        if (matrix[i][0] == 0 || matrix[0][j] == 0)
          matrix[i][j] = 0;
    // Fill 0s for the 1st row if needed
    if (shouldFillFirstRow)
      for (int j = 0; j < n; ++j)
        matrix[0][j] = 0;
    // Fill 0s for the 1st col if needed
    if (shouldFillFirstCol)
      for (int i = 0; i < m; ++i)
        matrix[i][0] = 0;
  }
}

Note: This problem Set Matrix Zeroes is generated by Leetcode but the solution is provided by  BrokenProgrammers. This tutorial is only for Educational and Learning purposes.

Next: Find First and Last Position of Element in Sorted Array Leetcode Solution

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