Step 2 of 6

Formatting tables with iomanip

Printing numbers in neat columns needs control over width, alignment and decimal places. In C that's printf("%-10s%6.2f"). In C++ it's the manipulators from <iomanip>:

Manipulator	Effect
`std::setw(n)`	pad the next item to width n (only the next one!)
`std::left`, `std::right`	alignment inside that width (sticky)
`std::fixed` + `std::setprecision(2)`	always 2 digits after the decimal point (sticky)
`std::setfill('0')`	pad with a character other than space (sticky)

"Sticky" settings stay on the stream until you change them. setw resets after each item.

#include <iomanip>
#include <iostream>

int main() {
    std::cout << std::fixed << std::setprecision(2);
    std::cout << std::left << std::setw(8) << "item" << std::right << std::setw(8) << "price" << "\n";
    std::cout << std::left << std::setw(8) << "tea" << std::right << std::setw(8) << 3.5 << "\n";
    std::cout << std::left << std::setw(8) << "cake" << std::right << std::setw(8) << 12.999 << "\n";
    std::cout << std::setfill('0') << std::setw(2) << 7 << ":" << std::setw(2) << 5 << "\n";
}

item       price
tea         3.50
cake       13.00
07:05

Reading the example

std::fixed << std::setprecision(2) is set once at the top and applies to every floating point number after it. Without std::fixed, setprecision(2) would mean "2 significant digits" and print 3.5 as 3.5 and 12.999 as 13.
std::setw(8) is written before every item that needs padding, because it only lasts for one item.
std::left and std::right are sticky, so a table that mixes alignments has to switch back and forth, as each row does here.
12.999 rounds to 13.00: setprecision rounds, it never just chops digits off.
If a value is wider than the setw, it's printed in full; the column just gets pushed over. Nothing is ever cut off.

The K/D detail in your task

kills / deaths with two ints does integer division. Convert one side first: static_cast<double>(kills) / d. And handle the "0 deaths counts as 1" rule before dividing.

Your turn: read name kills deaths rows and print a table: name left-aligned in 10 columns, kills and deaths right-aligned in 4 columns each, then the K/D ratio right-aligned in 6 columns with 2 decimals (use 0 deaths as 1 death).

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