# Count all the columns in a matrix which are sorted in descending

Given a matrix **mat[][]**, the task is to count the number of columns that are sorted in descending.

**Examples:**

Input:mat[][] = {{1, 3}, {0, 2}}

Output:2

First column: 1 > 0

Second column: 3 > 2

Hence, the count is 2

Input:mat[][] = {{2, 2}, {1, 3}}

Output:1

**Approach:** Traverse each column one by one and check if the **next element** ≥ **previous element** in the same column. If the condition is valid for all the possible elements then increment the **count** by **1**. After all the columns have been traversed, print the **count**.

Below is the implementation of the above approach:

## Python3

`# Python3 program to count the number of columns ` `# in a matrix that are sorted in descending ` ` ` `# Function to count the number of columns ` `# in a matrix that are sorted in descending ` `def` `countDescCol(A): ` ` ` ` ` `countOfCol ` `=` `0` ` ` ` ` `for` `col ` `in` `zip` `(` `*` `A): ` ` ` `if` `all` `(col[i] >` `=` `col[i ` `+` `1` `] ` `for` `i ` `in` `range` `(` `len` `(col) ` `-` `1` `)): ` ` ` `countOfCol ` `+` `=` `1` ` ` ` ` `return` `countOfCol ` ` ` `# Driver code ` `A ` `=` `[[` `1` `, ` `3` `], [` `0` `, ` `2` `]] ` `print` `(countDescCol(A)) ` |

*chevron_right*

*filter_none*

**Output:**

2

## Recommended Posts:

- Print index of columns sorted by count of zeroes in the Given Matrix
- Sorting rows of matrix in ascending order followed by columns in descending order
- Sorting rows of matrix in descending order followed by columns in ascending order
- Count columns to be deleted to make each row sorted
- Count all sorted rows in a matrix
- Count elements smaller than or equal to x in a sorted matrix
- Sum of columns of a 2-D Matrix where first element is odd
- Count Negative Numbers in a Column-Wise and Row-Wise Sorted Matrix
- Remove first X rows and columns from a matrix
- Interchange elements of first and last columns in matrix
- Count zeros in a row wise and column wise sorted matrix
- Remove any corner X rows and columns from a matrix
- Print all elements in sorted order from row and column wise sorted matrix
- heapq in Python to print all elements in sorted order from row and column wise sorted matrix
- Ways of filling matrix such that product of all rows and all columns are equal to unity

If you like GeeksforGeeks and would like to contribute, you can also write an article using contribute.geeksforgeeks.org or mail your article to contribute@geeksforgeeks.org. See your article appearing on the GeeksforGeeks main page and help other Geeks.

Please Improve this article if you find anything incorrect by clicking on the "Improve Article" button below.