// Multiple initializations in a loop expression

import <iostream>;

import <format>;

int main()

{

unsigned int limit {};

std::cout << "This program calculates n! and the sum of the integers "

<< "up to n for values 1 to limit.\n";

std::cout << "What upper limit for n would you like? ";

std::cin >> limit;

// The format string for all rows of the table

const auto table_format{ "{:>8} {:>8} {:>20}\n" };

// Output column headings

std::cout << std::format(table_format, "integer", "sum", "factorial");

for (unsigned long long n {1}, sum {}, factorial {1}; n <= limit; ++n)

{

sum += n; // Accumulate sum to current n

factorial *= n; // Calculate n! for current n

std::cout << std::format(table_format, n, sum, factorial);

}

}