1. Trace the following program and fill in the values of the involved variables in the for loop of octal2Decimal function. int octal2Decimal(const string& octal) { int decimalValue 0, octalDigit; for (int i = 0; i < octal.length(); i++) octalDigit = octal[i]- '0'; decimalValue = decimalValue * 8 + octalDigit; return decimalValue; int main() string octal = "34561"; cout << octal2Decimal(octal); return 0; decimalValue i octal[i] octalDigit 1st iteration 2nd iteration 3rd iteration 4th iteration 5th iteration

C/C++ compilers are constructed in a certain way. Please provide specific examples.

You are implementing a simple file system for an operating system for managing files and folders; similar to Windows or UNIX. Your design should follow the following guidelines       i)  The entire file system is represented by an object which is the reference to the root folder      ii)  Any folder in the file system may contain two types of items, folders (subfolder) and files and you want to treat both in the same way     iii) possible operations: getName, getPermission, listItem       What is the most appropriate design pattern?

Please elaborate on the meaning of "portability" in the context of different programming languages.