$1.$ Write a C$++$ program that does the following:

a$.$ Create a C$++$ file with the name problem$2.$cpp$.$

b$.$ Prompt the user to enter an integer in the range from $1$ to $100,$ validating the input until the user enters an integer from the range.

c$.$ Print the first $20$ multiples of the entered integer.

Sample run of the program:

Enter a number between $1$ and $100$: $102$

Invalid input!

Enter a number between $1$ and $100$: $3$

The first $20$ multiples of $3$ are $3691215182124273033363942454851545760.$

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