Visible Student Count in a Square Formation

As the sports secretary, C is responsible for training the honor guard for the sports meet. The honor guard is arranged in a square formation of size \(N \times N\) (with students standing in a grid). To ensure that the formation is perfectly aligned during the march, C stands at the left rear corner of the formation and counts the number of students visible along his line of sight.

When the formation is perfectly neat, the heights of the students are arranged in increasing order from left to right and from bottom to top. In such a configuration, the students that can be seen from the left rear corner are exactly those on the leftmost column and the bottom row. Since the student at the bottom left corner is counted twice, the total number of visible students is given by:

[ \text{Visible Count} = 2N - 1 ]

Your task is to compute and output the number \(2N-1\) given the value of \(N\).

inputFormat

The input consists of a single integer \(N\) representing the dimensions of the square formation.

outputFormat

Output a single integer, the number of students visible from the left rear corner, which is \(2N-1\).

sample

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