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C++ program to display prime numbers
In this program, we will read the value of N (range of the numbers) and print the all prime numbers from 2 to N.
To check prime numbers, we are creating a user defined function isPrime() that will take an integer number and return 1 if number is prime and 0 if number is not prime.
Program to display prime numbers in C++
#include <iostream>
using namespace std;
//function to check prime numbers
int isPrime(int num);
int main()
{
int i;
int n; //to store, maximum range
cout<<"Enter maximum range (n): ";
cin>>n;
//print prime numbers from 2 to n
cout<<"Prime numbers:"<<endl;
for(i=2;i<n;i++)
{
if(isPrime(i))
cout<<i<<" ";
}
cout<<endl;
return 0;
}
//function definition
int isPrime(int num)
{
int cnt;
int prime=1;
for(cnt=2;cnt<=(num/2);cnt++)
{
if(num%cnt==0)
{
prime=0;
break;
}
}
return prime;
}
Output
Enter maximum range (n): 100
Prime numbers:
2 3 5 7 11 13 17 19 23 29 31 37 41 43 47 53 59 61 67 71 73 79 83 89 97
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