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CPP program to check prime number

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The below program checks if a number is a prime or a composite number. The CPP cout object is used to output the result on the screen.

Code:

#include <iostream.h>
using namespace std;
 
int main()
{
int x,i;
int count = 0;    
 
cout << "Enter a number:";    
cin >> x;  
 
for (i=1; i<=x; i++)  
{
if ((x % i)==0)  
count++;  
}  
 
if (count<3)  
cout << x << " is a prime number.";  
 
else
cout << x << " is not a prime number.";  
 
return 0;
}

Output

Enter a number:13
13 is a prime number.