Mastermind Numeric Version
This is a C# console application that is a simplified version of Mastermind.
A randomly generated answer is a four digit number with each digit ranging between 1 and 6. The digits do not repeat.
After the player enters a combinatiokn, a minus(-) sign is printed for every digit that is correct but in a different position.
A plus(+) sign is printed for every digit that is correct and in a matching position. Nothing is printed for digits not in the
generated number. A player may attempt to guess the generated number up to 10 times before losing the game.