#### Reading the Input Data and Printing the First Row

We can see from the explanation that the input data will be taken from only one row which contains an integer in the interval [3 … 1000]. Therefore we will use a variable of type int.

We can divide the figure into 3 parts - upper, middle and lower. The upper part contains two subparts - first row and rows in which the sign widens. The first row is made of a beginning ., middle _ and an end .. After looking at the examples we can say that the beginning is n + 1 columns wide so it is good to write this value in a separate variable.

We must also create a second variable, in which we will keep the value of the middle of the first row, which is 2 * n + 1 columns wide.

After we have declared and initialized the two variables we can print the first row on the console.