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A positive integer n is called prime if it is not divisible by any positive integers other than 1 and n. For example, 7 is prime but 8 is not prime.
Write a function prime that returns true if a positive integer is prime, and returns false otherwise. For example, prime(7) should return true and prime(8) should return false.
Here is one strategy you could use for checking that a number is prime. (If you can think of a more efficient strategy you can use that instead.) To find out whether n is prime, you just need to check whether it is divisible by any of the numbers in between 1 and n. For example, to see whether 7 is prime, check whether it is divisible by 2, 3, 4, 5, or 6. (You will need a loop in your program to successively check each of these numbers.) Since it turns out that 7 is not divisible by any of these numbers, 7 is prime.
Your prime function must utilize the divisible function that you wrote for Assignment 17.
As usual, you will need to write a main program that tests the prime function. The program should allow the user to type a number, then tell the user whether or not that number is prime. Use a repeating structure in your main program that allows the user to do this repeatedly, until they type the number 0 indicating that they want to stop.
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