Răspuns :
3)
#include <iostream>
using namespace std;
int main() {
int a, b;
cin >> a >> b;
swap(a, b);
cout << a << " " << b;
return 0;
}
4)
#include <iostream>
#include <cmath>
using namespace std;
int main() {
int a, b, c;
float p;
cin >> a >> b >> c;
p = (a+b+c)/2
cout << "Primetrul triunghiului este " << p*2 << ".\n";
cout << "Aria triunghiului este " << sqrt(p * (p-a) * (p-b) * (p-c)) << ".";
return 0;
}
5)
#include <iostream>
using namespace std;
int main() {
float x1, x2, x3, x4, x5, temp;
cin >> x1 >> x2 >> x3 >> x4 >> x5;
temp = x1;
x1 = x2;
x2 = x3;
x3 = x4;
x4 = x5;
x5 = temp;
return 0;
}