Răspuns:
#include <iostream>
#include <cmath>
using namespace std;
int n;
int main ()
{
cin >> n;
if (n % 3 == 0) cout << "dublul numarului=" << n*2;
else cout << "jumatatea numarului=" << (float)n/2;
cout << endl;
if (n % 5 == 0) cout << "triplul numarului=" << n*3;
else cout << "succ si pred=" << n+1 << " " << n-1;
cout << endl;
if (n % 7 == 0) cout << "patratul numarului=" << n*n;
else cout << "radical din numar=" << (float) sqrt(n);
return 0;
}
