C++ Programming Code Examples
C++ > Mathematics Code Examples
Check the Number is Prime or Not
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/* Check the Number is Prime or Not
To check whether the number is a prime number or not a prime number in C++ programming, you have to ask to the user to enter a number and start checking for prime number. If number is divisible by 2 to one less than that number (n-1), then the number is not prime number, otherwise it will be a prime number. */
#include<iostream.h>
#include<conio.h>
void main()
{
clrscr();
int num,i,count=0;
cout<<"Enter a number:";
cin>>num;
for(i=2;i<num;i++)
{
if(num%i==0)
{
count++;
break;
}
}
if(count==0)
{
cout<<"This is a prime number";
}
else
{
cout<<"This is not a prime number";
}
getch();
}
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