RUN
C C++ JAVA PYTHON SQL HTML CSS DSA Robotics AWS SDE PREPARATION

Made with  & Code

# Count number of zeros in a Row-wise Col-wise sorted binary matrix

Written By -

Count number of zeros in a Row-wise Col-wise sorted binary matrix

Given: a binary matrix with sorted rows and columns.

Example: If the matrix is :

[0, 0, 0, 1]

[0, 0, 1, 1]

[0, 1, 1, 1]

[1, 1, 1, 1]

Then output should be 6, because there are 6 zeros in the matrix.

### # Approach

The entire matrix is traversed and the count of zeros is incremented.

Code:

``````#include <iostream>

// C++ program to count number of 0s in the given

// row-wise and column-wise sorted binary matrix.

// define size of square matrix

const int N = 5;

// Function to count number of 0s in the given

// row-wise and column-wise sorted binary matrix.

int zerocount(int mat[N][N])

{

// starting from bottom -left corner of matrix

int rows = N - 1, column = 0;

// variable storing number of zeroes

int count = 0;

while (column < N)

{

// going up till we find a 0

while (mat[rows][column])

//we are done

if (--rows < 0)

return count;

// add number of 0s present in current column to the answer

count += (rows + 1);

// moving right to next the column

column++;
}

return count;

}

// main function

int main()

{

int mat[N][N] =

{

{ 0, 0, 0, 0, 0 },
{ 0, 0, 0, 1, 1 },
{ 0, 0, 0, 1, 1 },
{ 0, 0, 1, 1, 1 },
{ 1, 1, 1, 1, 1 }
};

std::cout << zerocount(mat);

return 0;

}``````

TIME COMPLEXITY: The time complexity of this code is O(n2)