# 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)) ` |

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*filter_none*

**Output:**

2

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