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cout<<i<<"
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for(i=10;i<=20;i++)
cout << i << " ";
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#include <iostream>
#include <math.h>
using namespace std;
int main() {
int n; //
int i; //
int is_prime; // ,
is_prime = true;
//
cout << "Enter a number and press ENTER: ";
cin >> n;
//
for (i = 2; i <= sqrt((double) n); i++) {
if (n % i == 0)
is_prime = false;
}
//
if (is_prime)
cout << "Number is prime.";
else
cout << "Number is not prime.";
return 0;
}
: sqrt((double) n) n.
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✓ n , square_root_of_n for. , double.
✓ n, . , if break ( ) is_prime false.
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x ( x double).