Код на C++:
#include <iostream>
#include <ctime>
using namespace std;
int main()
{
setlocale(LC_ALL, "rus");
srand(time(NULL));
int rows = 30;
int chairs = 0;
for (int i = 1, count_of_chairs = 20; i <= 30; i++, count_of_chairs += 2)
{
chairs += count_of_chairs;
}
cout << chairs << endl;
return 0;
};
Код на Python:
rows = 30
chairs = 0
count_of_chairs = 20
for i in range(1, 31, 1):
chairs += count_of_chairs
count_of_chairs += 2
print(chairs)
Объяснение: