Chapter 25 // Drill 3, 4, 5 - Principles & Practice Using C++

In this exercise I am using Visual Studio 2019 and a modified version of the std_lib_facilities header found here.

Chapter 25 // Drill 3

Using hexadecimal literals, define short unsigned ints with:

• Every bit set
• The lowest (least significant bit) set
• The highest (most significant bit) set
• The lowest byte set
• The highest byte set
• Every second bit set (and the lowest bit 1)
• Every second bit set (and the lowest bit 0)

Chapter 25 // Drill 4

Print each as a decimal and as a hexadecimal.

Chapter 25 // Drill 5

Do 3 and 4 using bit manipulation operations (|, &, <<) and (only) the literals 1 and 0.

Github: https://github.com/l-paz91/principles-practice/blob/master/Chapter%2025/Drills/Drills%203%2C4%2C5

I cheated with drill 3 and just wrote out the binary then converted it to hex using 

https://www.rapidtables.com/convert/number/binary-to-hex.html

5 was annoying because you can directly type out binary literals in C++14 and assign them to things. The challenge came from only using 1 and 0. Like setting the highest byte can be done with 1 << 15 but 15 isn't 1 or 0.

I honestly had no idea how to do the last 2 using only 1 and 0, so I cheated and just used direct binary strings.

Chapter 25 // Drill 1, 2 - Principles & Practice Using C++

In this exercise I am using Visual Studio 2019 and a modified version of the std_lib_facilities header found here.

Chapter 25 // Drill 1

Run this:

int v = 1; for(int i = 0; i < sizeof(v)*8; ++i) { cout << v << ' '; v << =1; }

I've never seen <<= before. But shifting to the left by 1 is the "cheapest" and "fastest" way to multiply by 2. In some very low-level engine code at work, I often see >> 1 to divide by 2 instead of / 2, however it's not 1995 anymore and Visual Studio will convert divides/multiplies that are powers of 2 to an equivalent shift for you.

The last number will wrap as it's 1 over the max limit of a signed int.

Chapter 25 // Drill 2

Run that again with v declared to be an unsigned int.

Github: https://github.com/l-paz91/principles-practice/blob/master/Chapter%2025/Drills/Drill%201%2C2

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