Triangular Number Series

Given an integer n, your task is to compute the nth term of the triangular number series. The triangular number is defined as the sum of the first n natural numbers. It can be computed using the formula: \(\frac{n(n+1)}{2}\).

For example, the 4th triangular number is 10, since \(1 + 2 + 3 + 4 = 10\).

inputFormat

The input consists of a single line containing an integer n (1 ≤ n ≤ 10⁵), representing the term of the triangular number series you need to calculate.

outputFormat

Output a single integer which is the nth triangular number.

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