The value of $$ can be approximated by using the following series:

$=4(1-\frac{1}{3}+\frac{1}{5}-\frac{1}{7}+$cdots$+\frac{1}{2n-1}+\frac{1}{2n+1})$

The program in main.cpp uses this series to find the approximate value of $$ However, the statements are in the incorrect order, and there is also a bug in this program.

Rearrange the statements and remove the bug so that this program can be used to approximate $.$ IN C$++$