Second Smallest Unique Integer

Given a list of integers, your task is to determine the second smallest unique integer. If there are less than two unique integers in the list, print -1.

You are given a single line of input consisting of space-separated integers. The output should be the second smallest number among the unique integers, or -1 if the condition is not met.

In mathematical terms, if the set of unique integers is \( S \) and \(|S| \ge 2\), then you need to output the second smallest element in the sorted order of \( S \). Otherwise, output \( -1 \).

inputFormat

The input consists of a single line containing space-separated integers.

For example:

5 3 9 1 4 3

outputFormat

Output a single integer --- the second smallest unique integer among the given numbers, or -1 if there are less than two unique integers.

5 3 9 1 4 3

3