Given an integer **N**, the task is to find the minimum number of digits required to generate a number having the sum of digits equal to **N**.

**Examples:**

Input:N = 18Output:2Explanation:

The number with smallest number of digits having sum of digits equal to 18 is 99.

Input:N = 28Output:4Explanation:

4-digit numbers like 8884, 6877, etc are the smallest in length having sum of digits equal to 28.

**Approach: **The problem can be solved by the following observations:

- Increment
**count**by**9**. Therefore, now count is equal to the number of 9’s in the shortest number. Reduce**N**to**N % 9** - Now, if
**N**exceeds 0, increment**count**by**1**. - Finally, print
**count**as the answer.

Below is the implementation of the above approach:

## C++

`// C++ program to implement` `// the above approach` `#include <bits/stdc++.h>` `using` `namespace` `std;` `// Function to return the` `// minimum count of digits` `void` `mindigits(` `int` `n)` `{` ` ` `// IF N is divisible by 9` ` ` `if` `(n % 9 == 0) {` ` ` `// Count of 9's is the answer` ` ` `cout << n / 9 << endl;` ` ` `}` ` ` `else` `{` ` ` `// If remainder is non-zero` ` ` `cout << (n / 9) + 1 << endl;` ` ` `}` `}` `// Driver Code` `int` `main()` `{` ` ` `int` `n1 = 24;` ` ` `int` `n2 = 14;` ` ` `mindigits(n1);` ` ` `mindigits(n2);` `}` |

## Java

`// Java program to implement` `// the above approach` `// required to make the given sum` `import` `java.util.*;` `class` `Main {` ` ` `// Function to print the minimum` ` ` `// count of digits` ` ` `static` `void` `mindigits(` `int` `n)` ` ` `{` ` ` `// IF N is divisible by 9` ` ` `if` `(n % ` `9` `== ` `0` `) {` ` ` `// Count of 9's is the answer` ` ` `System.out.println(n / ` `9` `);` ` ` `}` ` ` `else` `{` ` ` `// If remainder is non-zero` ` ` `System.out.println((n / ` `9` `) + ` `1` `);` ` ` `}` ` ` `}` ` ` `// Driver Code` ` ` `public` `static` `void` `main(String[] args)` ` ` `{` ` ` `int` `n1 = ` `24` `;` ` ` `int` `n2 = ` `18` `;` ` ` `mindigits(n1);` ` ` `mindigits(n2);` ` ` `}` `}` |

## Python3

`# Python3 program to implement` `# the above approach` `# Function to print the minimum` `# count of digits` `def` `mindigits(n):` ` ` ` ` `# IF N is divisible by 9` ` ` `if` `(n ` `%` `9` `=` `=` `0` `):` ` ` `# Count of 9's is the answer` ` ` `print` `(n ` `/` `/` `9` `);` ` ` `else` `:` ` ` `# If remainder is non-zero` ` ` `print` `((n ` `/` `/` `9` `) ` `+` `1` `);` `# Driver Code` `if` `__name__ ` `=` `=` `'__main__'` `:` ` ` ` ` `n1 ` `=` `24` `;` ` ` `n2 ` `=` `18` `;` ` ` ` ` `mindigits(n1);` ` ` `mindigits(n2);` `# This code is contributed by amal kumar choubey` |

## C#

`// C# program to implement` `// the above approach` `using` `System;` `class` `GFG{` `// Function to print the minimum` `// count of digits` `static` `void` `mindigits(` `int` `n)` `{` ` ` ` ` `// IF N is divisible by 9` ` ` `if` `(n % 9 == 0)` ` ` `{` ` ` ` ` `// Count of 9's is the answer` ` ` `Console.WriteLine(n / 9);` ` ` `}` ` ` `else` ` ` `{` ` ` ` ` `// If remainder is non-zero` ` ` `Console.WriteLine((n / 9) + 1);` ` ` `}` `}` `// Driver Code` `public` `static` `void` `Main(String[] args)` `{` ` ` `int` `n1 = 24;` ` ` `int` `n2 = 18;` ` ` ` ` `mindigits(n1);` ` ` `mindigits(n2);` `}` `}` `// This code is contributed by 29AjayKumar` |

## Javascript

`<script>` `// JavaScript program to implement` `// the above approach` `// required to make the given sum` ` ` `// Function to print the minimum` ` ` `// count of digits` ` ` `function` `mindigits(n)` ` ` `{` ` ` ` ` `// IF N is divisible by 9` ` ` `if` `(n % 9 == 0) {` ` ` ` ` `// Count of 9's is the answer` ` ` `document.write(Math.floor(n / 9) + ` `"<br/>"` `);` ` ` `}` ` ` `else` `{` ` ` ` ` `// If remainder is non-zero` ` ` `document.write(Math.floor(n / 9) + 1 + ` `"<br/>"` `);` ` ` `}` ` ` `}` `// Driver Code` ` ` `let n1 = 24;` ` ` `let n2 = 18;` ` ` `mindigits(n1);` ` ` `mindigits(n2);` ` ` `</script>` |

**Output:**

3 2

**Time Complexity:** O(1)**Auxiliary Space:** O(1)

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