Unique Sums from Two Distinct Elements

This problem requires you to compute all the unique sums that can be generated by adding two distinct elements from a given list of integers. For a list \( a_1, a_2, \dots, a_N \), consider all pairs \( (a_i, a_j) \) such that \( i < j \) and compute \( a_i + a_j \). Your task is to output all distinct sums sorted in non-decreasing order.

If no such pair exists, output nothing.

inputFormat

The input is provided via standard input (stdin) and consists of two lines:

• First line: An integer \( N \) representing the number of elements.
• Second line: \( N \) space-separated integers representing the elements of the list.

outputFormat

Print the unique sums obtained by adding every pair of distinct elements, with each sum on a new line, sorted in non-decreasing order. If no valid pair exists, output nothing.

## sample

4
1 2 3 4

3
4
5
6
7

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