Calculate Mode of a List

Given a list of integers, determine the mode of the list. The mode is defined as the number or numbers that appear most frequently. If there is a single mode, output that integer; if there are multiple modes, output all of them in ascending order separated by a space.

If the input list is empty, output the error message "The list is empty".

For example:

• Input: 1 2 2 3 3 → Output: 2 3
• Input: 4 4 4 1 2 2 3 → Output: 4

The mathematical condition can be written as: $$ \max_{x \in S} \; \#\{i : S_i = x\} $$ where if more than one $x$ attains the maximum frequency, they should be output in sorted order.

inputFormat

The input is provided via standard input (stdin) as a single line containing space-separated integers.

outputFormat

If there is a single mode, output that number. If there are multiple modes, output them as space-separated integers in ascending order. If the input list is empty, output "The list is empty".

4 4 4 1 2 2 3

4