# Tidy Number (Digits in non-decreasing Order)

• Difficulty Level : Basic
• Last Updated : 22 Mar, 2021

Given a number, the task is to check if it is tidy or not. A tidy number is a number whose digits are in non-decreasing order.
Examples :

```Input : 1234
Output : Yes

Input : 1243
Output : No
Digits "4" and "3" violate the property.```

Algorithm:

```1- One by one find all the digits.
2- Compare every digit with its next digit.
3- If any is in decreasing order then return false.
4- Otherwise return true.```

Implementation :

## C++

 `// C++ program to check if a number is Tidy``// or not.``#include``using` `namespace` `std;` `// Returns true if num is Tidy``bool` `isTidy(``int` `num)``{``    ``// To store previous digit (Assigning``    ``// initial value which is more than any``    ``// digit)``    ``int` `prev = 10;` `    ``// Traverse all digits from right to``    ``// left and check if any digit is``    ``// smaller than previous.``    ``while` `(num)``    ``{``        ``int` `rem = num % 10;``        ``num /= 10;``        ``if` `(rem > prev)``           ``return` `false``;``        ``prev = rem;``    ``}` `    ``return` `true``;``}` `// Driver code``int` `main()``{``    ``int` `num = 1556;``    ``isTidy(num) ? cout << ``"Yes"``                ``: cout << ``"No"``;``    ``return` `0;``}`

## Java

 `// Java program to check if a number``// is Tidy or not.` `class` `Test``{``    ``// Returns true if num is Tidy``    ``static` `boolean` `isTidy(``int` `num)``    ``{``        ``// To store previous digit``        ``// (Assigning initial value``            ``// which is more than any``        ``// digit)``        ``int` `prev = ``10``;``     ` `        ``// Traverse all digits from right to``        ``// left and check if any digit is``        ``// smaller than previous.``        ``while` `(num!=``0``)``        ``{``            ``int` `rem = num % ``10``;``            ``num /= ``10``;``            ``if` `(rem > prev)``               ``return` `false``;``            ``prev = rem;``        ``}``     ` `        ``return` `true``;``    ``}``    ` `    ``// Driver method``    ``public` `static` `void` `main(String[] args)``    ``{``        ``int` `num = ``1556``;``        ``System.out.println(isTidy(num) ? ``"Yes"` `: ``"No"``);``    ``}``}`

## Python3

 `# Python program to check if a number``# is Tidy or not.` `# Returns true if num is Tidy``def` `isTidy(num):` `    ``# To store previous digit (Assigning``    ``# initial value which is more than any``    ``# digit)``    ``prev ``=` `10``    ` `    ``# Traverse all digits from right to``    ``# left and check if any digit is``    ``# smaller than previous.``    ``while` `(num):``        ``rem ``=` `num ``%` `10``        ``num ``/``=` `10``        ``if` `rem > prev:``            ``return` `False``        ``prev ``=` `rem``    ``return` `True` `# Driver code``num ``=` `1556``if` `isTidy(num):``    ``print``(``"Yes"``)``else``:``    ``print``(``"No"``)` `# This code is contributed by Sharad_Bhardwaj.`

## C#

 `// C# program to check if a``// number is Tidy or not.``using` `System;` `class` `GFG``{``    ``// Returns true if num is Tidy``    ``static` `bool` `isTidy(``int` `num)``    ``{``        ``// To store previous digit``        ``// (Assigning initial value``        ``// which is more than any``        ``// digit)``        ``int` `prev = 10;``    ` `        ``// Traverse all digits from``        ``// right to left and check``        ``// if any digit is smaller``        ``// than previous.``        ``while` `(num != 0)``        ``{``            ``int` `rem = num % 10;``            ``num /= 10;``            ``if` `(rem > prev)``            ``return` `false``;``            ``prev = rem;``        ``}``    ` `        ``return` `true``;``    ``}``    ` `// Driver Code``public` `static` `void` `Main ()``{``    ``int` `num = 1556;` `    ``Console.WriteLine(isTidy(num) ?``                            ``"Yes"` `:``                             ``"No"``);``}``}` `// This code is contributed by m_kit`

## PHP

 ` ``\$prev``)``            ``return` `false;``        ``\$prev` `= ``\$rem``;``    ``}` `    ``return` `true;``}` `// Driver code``\$num` `= 1556;``if``(isTidy(``\$num``) == true)``echo` `"Yes"``;``else``echo` `"No"``;` `// This code is contributed by aj_36``?>`

## Javascript

 ``

Output :

`Yes`

Time Complexity : O(d) where d is number of digits in given number.
Reference :
https://www.careercup.com/question?id=5136136486780928
This article is contributed by Sahil Chhabra (akku). If you like GeeksforGeeks and would like to contribute, you can also write an article using write.geeksforgeeks.org or mail your article to review-team@geeksforgeeks.org. See your article appearing on the GeeksforGeeks main page and help other Geeks.