# Sort Matrix in alternating ascending and descending order rowwise

Given an N x N matrix, our task is to print the row of the matrix in ascending and descending order alternatively.
Examples:

Input:
5 7 3 4
9 5 8 2
6 3 8 1
5 8 9 3
Output:
3 4 5 7
9 8 5 2
1 3 6 8
9 8 5 3
Explanation:
Here the first row is sorted in ascending order, second row sorted in descending order, third row sorted in ascending order and so on.
Input:
7 3 4
3 8 2
3 6 1
Output:
3 4 7
8 3 2
1 3 6
Explanation:
Here the first row is sorted in ascending order, second row sorted in descending order, third row sorted in ascending order.

Approach to solve
To solve the problem mentioned above we iterate 0 to N and check if the ith row is even or odd, if it is even then we sort the row in ascending order otherwise sort the ith row in descending order. Return the matrix after N iterations.
Below is the implementation of the above approach:

## C++

 `// C++ implementation to print row of` `// matrix in ascending or descending` `// order alternatively`   `#include ` `#define N 4`   `void` `func(``int` `a[][N])` `{`   `    ``// Iterate matrix rowwise` `    ``for` `(``int` `i = 0; i < N; i++) {`   `        ``// Sort even rows in ascending order` `        ``if` `(i % 2 == 0) {` `            ``for` `(``int` `j = 0; j < N; j++) {` `                ``for` `(``int` `k = j + 1; k < N; ++k) {`   `                    ``// compare adjacent elements` `                    ``if` `(a[i][j] > a[i][k]) {`   `                        ``// swap adjacent element` `                        ``int` `temp = a[i][j];` `                        ``a[i][j] = a[i][k];` `                        ``a[i][k] = temp;` `                    ``}` `                ``}` `            ``}` `        ``}`   `        ``// Sort even rows in descending order` `        ``else` `{` `            ``for` `(``int` `j = 0; j < N; j++) {` `                ``for` `(``int` `k = j + 1; k < N; ++k) {`   `                    ``// compare adjacent elements` `                    ``if` `(a[i][j] < a[i][k]) {`   `                        ``// swap adjacent element` `                        ``int` `temp = a[i][j];` `                        ``a[i][j] = a[i][k];` `                        ``a[i][k] = temp;` `                    ``}` `                ``}` `            ``}` `        ``}` `    ``}`   `    ``// Printing the final Output` `    ``for` `(``int` `i = 0; i < N; i++) {` `        ``for` `(``int` `j = 0; j < N; j++) {` `            ``printf``(``"%d "``, a[i][j]);` `        ``}` `        ``printf``(``"\n"``);` `    ``}` `}`   `// Driver code` `int` `main()` `{`   `    ``int` `a[N][N] = {` `        ``{ 5, 7, 3, 4 },` `        ``{ 9, 5, 8, 2 },` `        ``{ 6, 3, 8, 1 },` `        ``{ 5, 8, 9, 3 }` `    ``};`   `    ``func(a);`   `    ``return` `0;` `}`

## Java

 `// Java implementation to print row of` `// matrix in ascending or descending` `// order alternatively` `class` `GFG{` `    `  `static` `int` `N = ``4``;`   `static` `void` `func(``int` `a[][])` `{` `    ``int` `i, j, k;` `    `  `    ``// Iterate matrix rowwise` `    ``for``(i = ``0``; i < N; i++)` `    ``{` `        `  `       ``// Sort even rows in ascending order` `       ``if` `(i % ``2` `== ``0``)` `       ``{` `           ``for``(j = ``0``; j < N; j++) ` `           ``{` `              ``for``(k = j + ``1``; k < N; ++k) ` `              ``{` `                  `  `                 ``// Compare adjacent elements` `                 ``if` `(a[i][j] > a[i][k])` `                 ``{` `                     `  `                     ``// Swap adjacent element` `                     ``int` `temp = a[i][j];` `                     ``a[i][j] = a[i][k];` `                     ``a[i][k] = temp;` `                 ``}` `              ``}` `           ``}` `       ``}` `       `  `       ``// Sort even rows in descending order` `       ``else` `       ``{` `           ``for``(j = ``0``; j < N; j++) ` `           ``{` `              ``for``(k = j + ``1``; k < N; ++k)` `              ``{` `                  `  `                 ``// Compare adjacent elements` `                 ``if` `(a[i][j] < a[i][k])` `                 ``{` `                     `  `                     ``// Swap adjacent element` `                     ``int` `temp = a[i][j];` `                     ``a[i][j] = a[i][k];` `                     ``a[i][k] = temp;` `                 ``}` `              ``}` `           ``}` `       ``}` `    ``}` `    `  `    ``// Printing the final Output` `    ``for``(i = ``0``; i < N; i++)` `    ``{` `       ``for``(j = ``0``; j < N; j++)` `       ``{` `          ``System.out.print(a[i][j] + ``" "``);` `       ``}` `       ``System.out.print(``"\n"``);` `    ``}` `}`   `// Driver code` `public` `static` `void` `main (String []args)` `{`   `    ``int` `a[][] = { { ``5``, ``7``, ``3``, ``4` `},` `                  ``{ ``9``, ``5``, ``8``, ``2` `},` `                  ``{ ``6``, ``3``, ``8``, ``1` `},` `                  ``{ ``5``, ``8``, ``9``, ``3` `} };`   `    ``func(a);` `}` `}`   `// This code is contributed by chitranayal`

## Python3

 `# Python3 implementation to print row of` `# matrix in ascending or descending` `# order alternatively` `N ``=` `4`   `def` `func(a):` `    `  `    ``# Iterate matrix rowwise` `    ``for` `i ``in` `range``(N):`   `        ``# Sort even rows in ascending order` `        ``if` `i ``%` `2` `=``=` `0``:` `            ``for` `j ``in` `range``(N):` `                ``for` `k ``in` `range``(j ``+` `1``, N):` `                    `  `                    ``# Compare adjacent elements` `                    ``if` `a[i][j] > a[i][k]:` `                        `  `                        ``# Swap adjacent element` `                        ``temp ``=` `a[i][j]` `                        ``a[i][j] ``=` `a[i][k]` `                        ``a[i][k] ``=` `temp`   `        ``# Sort even rows in descending order` `        ``else` `:` `            ``for` `j ``in` `range``(N):` `                ``for` `k ``in` `range``(j ``+` `1``, N):`   `                    ``# Compare adjacent elements` `                    ``if` `a[i][j] < a[i][k]:`   `                        ``# Swap adjacent element` `                        ``temp ``=` `a[i][j]` `                        ``a[i][j] ``=` `a[i][k]` `                        ``a[i][k] ``=` `temp`   `    ``# Printing the final output` `    ``for` `i ``in` `range``(N):` `        ``for` `j ``in` `range``(N):` `            ``print``(a[i][j], end ``=` `" "``)` `        ``print``()` `        `  `# Driver code` `if` `__name__ ``=``=` `'__main__'``:`   `    ``a ``=` `[ [ ``5``, ``7``, ``3``, ``4` `],` `          ``[ ``9``, ``5``, ``8``, ``2` `],` `          ``[ ``6``, ``3``, ``8``, ``1` `],` `          ``[ ``5``, ``8``, ``9``, ``3` `] ]` `          `  `    ``func(a)`   `# This code is contributed by mohit kumar 29`

## C#

 `// C# implementation to print row of` `// matrix in ascending or descending` `// order alternatively` `using` `System;` `class` `GFG{` `    `  `static` `int` `N = 4;`   `static` `void` `func(``int``[,]a)` `{` `    ``int` `i, j, k;` `    `  `    ``// Iterate matrix rowwise` `    ``for``(i = 0; i < N; i++)` `    ``{` `        `  `       ``// Sort even rows in ascending order` `       ``if` `(i % 2 == 0)` `       ``{` `           ``for``(j = 0; j < N; j++) ` `           ``{` `              ``for``(k = j + 1; k < N; ++k) ` `              ``{` `                  `  `                 ``// Compare adjacent elements` `                 ``if` `(a[i, j] > a[i, k])` `                 ``{` `                     `  `                     ``// Swap adjacent element` `                     ``int` `temp = a[i, j];` `                     ``a[i, j] = a[i, k];` `                     ``a[i, k] = temp;` `                 ``}` `              ``}` `           ``}` `       ``}` `       `  `       ``// Sort even rows in descending order` `       ``else` `       ``{` `           ``for``(j = 0; j < N; j++) ` `           ``{` `              ``for``(k = j + 1; k < N; ++k)` `              ``{` `                  `  `                 ``// Compare adjacent elements` `                 ``if` `(a[i, j] < a[i, k])` `                 ``{` `                     `  `                     ``// Swap adjacent element` `                     ``int` `temp = a[i, j];` `                     ``a[i, j] = a[i, k];` `                     ``a[i, k] = temp;` `                 ``}` `              ``}` `           ``}` `       ``}` `    ``}` `    `  `    ``// Printing the readonly Output` `    ``for``(i = 0; i < N; i++)` `    ``{` `       ``for``(j = 0; j < N; j++)` `       ``{` `          ``Console.Write(a[i, j] + ``" "``);` `       ``}` `       ``Console.Write(``"\n"``);` `    ``}` `}`   `// Driver code` `public` `static` `void` `Main(String []args)` `{`   `    ``int``[,]a = { { 5, 7, 3, 4 },` `                ``{ 9, 5, 8, 2 },` `                ``{ 6, 3, 8, 1 },` `                ``{ 5, 8, 9, 3 } };`   `    ``func(a);` `}` `}`   `// This code is contributed by Princi Singh`

Output:

```3 4 5 7
9 8 5 2
1 3 6 8
9 8 5 3

```

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