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Module DEMO-32-59DEMO-C-32

Prime Number Checker using for

DEMO-C-32 • Programming in C

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Problem Statement

Write a C program that reads a positive integer from the user and determines whether it is a prime number.

A prime number is a natural number greater than 1 that has no positive divisors other than 1 and itself.

Your program must use a loop to check for divisibility. Output one of the following messages based on the result:

  • PRIME if the number is prime.
  • NOT PRIME if the number is not prime.
  • INVALID INPUT if the number is less than or equal to 1.

Examples:

  • 2 is prime.
  • 4 is not prime (divisible by 2).
  • 1 is not prime (not greater than 1).

Input Format

A single line containing an integer n (1 <= n <= 10000).

Output Format

Print exactly one of the following strings:

  • PRIME
  • NOT PRIME
  • INVALID INPUT

Sample Testcases

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Sample #1
Public sample
Input
2
Output
PRIME
Explanation
2 is the smallest prime number.
Sample #2
Public sample
Input
17
Output
PRIME
Explanation
17 is a prime number with no divisors other than 1 and 17.
Sample #3
Public sample
Input
4
Output
NOT PRIME
Explanation
4 is divisible by 2, so it's not prime.
Sample #4
Public sample
Input
100
Output
NOT PRIME
Explanation
100 is divisible by 2, 4, 5, etc., so it's not prime.
Sample #5
Public sample
Input
1
Output
INVALID INPUT
Explanation
1 is not greater than 1, so it's not considered a prime number.

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