How to distinguish prime numbers

How to distinguish prime numbers

Prime number, also known as prime number, has infinite numbers. A natural number greater than 1, except 1 and itself, can not be divided by other natural numbers (except 0) is called prime number; otherwise, it is called composite number

How to judge prime number

Prime numbers are numbers that can only be divisible by 1 and themselves

Judge prime
Enter a positive integer n, and then enter n positive integers to determine whether they are prime
I only know one, I don't know how to cycle in it
For advice:
#include
#include
int main(void)
{
int i,m;
printf("enter a number:");
scanf("%d",&m);
for(i=2;im/2)
printf("%d is a prime number!/n",m);
else
printf("no!/n");
system("pause");
return 0;
}
If you can, let's look at this question again
Output all prime numbers between 101 and 200, 8 per line. A prime number is a positive integer that can only be divided by 1 and itself. 1 is not a prime number, 2 is a prime number
Do you use lower and upper? If so, how can you add them in

#include
int main()
{
int n,a[20],i,j;
Printf ("enter the number of items to be judged: n");
scanf("%d",&n);
Printf ("enter these numbers: n");
for(i=0;i