Prime Number in C

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Q. Write a C program to check Prime Number or Not.

#include 
void main()
{
    int n, i, flag = 0;
    printf("Enter the number: ");
    scanf("%d", &n);
    for(i = 2; i <= n/2; i++)
    {
        if(n%i == 0)
        {
            flag = 1;
            break;
        }
    }
    if ( n<=1) 
    {
      printf("Prime number is greater than 1.");
    }
    else 
    {
        if (flag == 0)
          printf("%d is a prime number.", n);
        else
          printf("%d is not a prime number.", n);
    }
}
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Q. Write an algorithm to check Prime Number or Not.

1. Start
2. Prompt the user to enter an integer `n`.
3. Read the input value `n`.
4. If `n` is less than or equal to 1:
   - Print "Prime number is greater than 1."
   - Stop.
5. Initialize a flag variable `flag = 0` to indicate whether a divisor is found.
6. For `i` from 2 to `n/2`:
   - If `n % i == 0` (i.e., `n` is divisible by `i`):
   - Set `flag = 1` (not prime)
   - Break the loop
7. After the loop:
   - If `flag` is 0:
   - Print "`n` is a prime number."
   - Else:
   - Print "`n` is not a prime number."
8. End
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