Related Articles
Product of N with its largest odd digit
• Last Updated : 25 Mar, 2021

Given an integer N, the task is to find the product of N with its largest odd digit. If there is no odd digit in N then print -1 as the output.
Examples:

Input: 12345
Output: 61725
The largest odd digit in 12345 is 5 and 12345 * 5 = 61725
Input: 24068
Output: -1

Approach: Traverse through all the digits of N and set maxOdd = -1, if current digit is odd and > maxOdd then update maxOdd = current digit
If in the end, maxOdd = -1 then print -1 else print N * maxOdd.
Below is the implementation of the above approach:

## C++

 `// C++ program to find the product of N``// with its largest odd digit``#include ``using` `namespace` `std;` `// Function to return the largest odd digit in n``int` `largestOddDigit(``int` `n)``{``    ``// If all digits are even then -1 will be returned``    ``int` `maxOdd = -1;``    ``while` `(n > 0) {` `        ``// Last digit from n``        ``int` `digit = n % 10;` `        ``// If current digit is odd and > maxOdd``        ``if` `(digit % 2 == 1 && digit > maxOdd)``            ``maxOdd = digit;` `        ``// Remove last digit``        ``n = n / 10;``    ``}` `    ``// Return the maximum odd digit``    ``return` `maxOdd;``}` `// Function to return the product of n``// with its largest odd digit``int` `getProduct(``int` `n)``{``    ``int` `maxOdd = largestOddDigit(n);` `    ``// If there are no odd digits in n``    ``if` `(maxOdd == -1)``        ``return` `-1;` `    ``// Product of n with its largest odd digit``    ``return` `(n * maxOdd);``}` `// Driver code``int` `main()``{``    ``int` `n = 12345;``    ``cout << getProduct(n);``    ``return` `0;``}`

## Java

 `// Java program to find the product of N``// with its largest odd digit` `class` `GFG``{``    ` `// Function to return the largest``// odd digit in n``static` `int` `largestOddDigit(``int` `n)``{``    ``// If all digits are even then -1``    ``// will be returned``    ``int` `maxOdd = -``1``;``    ``while` `(n > ``0``)``    ``{` `        ``// Last digit from n``        ``int` `digit = n % ``10``;` `        ``// If current digit is odd and > maxOdd``        ``if` `(digit % ``2` `== ``1` `&& digit > maxOdd)``            ``maxOdd = digit;` `        ``// Remove last digit``        ``n = n / ``10``;``    ``}` `    ``// Return the maximum odd digit``    ``return` `maxOdd;``}` `// Function to return the product of n``// with its largest odd digit``static` `int` `getProduct(``int` `n)``{``    ``int` `maxOdd = largestOddDigit(n);` `    ``// If there are no odd digits in n``    ``if` `(maxOdd == -``1``)``        ``return` `-``1``;` `    ``// Product of n with its largest odd digit``    ``return` `(n * maxOdd);``}` `// Driver code``public` `static` `void` `main(String[] args)``{``    ``int` `n = ``12345``;``    ``System.out.println(getProduct(n));``}``}` `// This code is contributed by chandan_jnu`

## Python3

 `# Python3 program to find the product``# of N with its largest odd digit` `# Function to return the largest``# odd digit in n``def` `largestOddDigit(n) :` `    ``# If all digits are even then -1``    ``# will be returned``    ``maxOdd ``=` `-``1``    ``while` `(n > ``0``) :` `        ``# Last digit from n``        ``digit ``=` `n ``%` `10` `        ``# If current digit is odd and > maxOdd``        ``if` `(digit ``%` `2` `=``=` `1` `and` `digit > maxOdd) :``            ``maxOdd ``=` `digit` `        ``# Remove last digit``        ``n ``=` `n ``/``/` `10` `    ``# Return the maximum odd digit``    ``return` `maxOdd` `# Function to return the product``# of n with its largest odd digit``def` `getProduct(n) :` `    ``maxOdd ``=` `largestOddDigit(n)` `    ``# If there are no odd digits in n``    ``if` `(maxOdd ``=``=` `-``1``) :``        ``return` `-``1` `    ``# Product of n with its largest``    ``# odd digit``    ``return` `(n ``*` `maxOdd)` `# Driver code``if` `__name__ ``=``=` `"__main__"` `:` `    ``n ``=` `12345``    ``print``(getProduct(n))` `# This code is contributed by Ryuga`

## C#

 `// C# program to find the product of N``// with its largest odd digit``using` `System;` `class` `GFG``{``    ` `// Function to return the largest``// odd digit in n``static` `int` `largestOddDigit(``int` `n)``{``    ``// If all digits are even then -1``    ``// will be returned``    ``int` `maxOdd = -1;``    ``while` `(n > 0)``    ``{` `        ``// Last digit from n``        ``int` `digit = n % 10;` `        ``// If current digit is odd and > maxOdd``        ``if` `(digit % 2 == 1 && digit > maxOdd)``            ``maxOdd = digit;` `        ``// Remove last digit``        ``n = n / 10;``    ``}` `    ``// Return the maximum odd digit``    ``return` `maxOdd;``}` `// Function to return the product of n``// with its largest odd digit``static` `int` `getProduct(``int` `n)``{``    ``int` `maxOdd = largestOddDigit(n);` `    ``// If there are no odd digits in n``    ``if` `(maxOdd == -1)``        ``return` `-1;` `    ``// Product of n with its largest odd digit``    ``return` `(n * maxOdd);``}` `// Driver code``public` `static` `void` `Main()``{``    ``int` `n = 12345;``    ``Console.Write(getProduct(n));``}``}` `// This code is contributed``// by Akanksha_Rai`

## PHP

 ` 0)``    ``{` `        ``// Last digit from n``        ``\$digit` `= ``\$n` `% 10;` `        ``// If current digit is odd and > maxOdd``        ``if` `(``\$digit` `% 2 == 1 && ``\$digit` `> ``\$maxOdd``)``            ``\$maxOdd` `= ``\$digit``;` `        ``// Remove last digit``        ``\$n` `= ``\$n` `/ 10;``    ``}` `    ``// Return the maximum odd digit``    ``return` `\$maxOdd``;``}` `// Function to return the product``// of n with its largest odd digit``function` `getProduct(``\$n``)``{``    ``\$maxOdd` `= largestOddDigit(``\$n``);` `    ``// If there are no odd digits in n``    ``if` `(``\$maxOdd` `== -1)``        ``return` `-1;` `    ``// Product of n with its largest``    ``// odd digit``    ``return` `(``\$n` `* ``\$maxOdd``);``}` `// Driver code``\$n` `= 12345;``echo` `getProduct(``\$n``);` `// This code is contributed``// by Akanksha Rai``?>`

## Javascript

 ``
Output:
`61725`

Attention reader! Don’t stop learning now. Get hold of all the important DSA concepts with the DSA Self Paced Course at a student-friendly price and become industry ready.

My Personal Notes arrow_drop_up