Given a number, write a program to find a maximum number that can be formed using all of the digits of this number.
Input : 38293367 Output : 98763332 Input : 1203465 Output: 6543210
Simple Approach: The simple method to solve this problem is to extract and store the digits of the given number in an integer array and sort this array in descending order. After sorting the array, print the elements of the array.
Time Complexity: O( N log N ), where N is the number of digits in the given number.
Efficient approach : We know that the digits in a number will range from 0-9, so the idea is to create a hashed array of size 10 and store the count of every digit in the hashed array that occurs in the number. Then traverse the hashed array from index 9 to 0 and calculate the number accordingly.
Below is the implementation of above efficient approach:
Time Complexity: O( N ), where N is the number of digits in the given number.
Note: For very large numbers we can use strings to take input instead of storing input in integer data type.
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