Integers

• Integer types represent the mathematical integer values
  • ... -3, -2, -1, 0, 1, 2, 3, ...
  • Both signed and unsigned.
• But the ... on either end is a problem
  • What does ... mean?
  • Why might we not be able to do this in a computer?
• Think about a football score board
  • 
  • What is the "highest" score you can have in the game
    • In theory?
    • According to the scoreboard?
  • This is a representation problem.
  • There is not enough space on the scoreboard
  • Are there scoreboards with more spaces?
• When C was invented, memory was expensive
  • So they created a bunch of different classes of integers.
  • If you know your values will be small, you can use a char or short.
  • If you know you want the biggest numbers available, use an unsigned long.
  • But int it just right for most things.
• Since the power and abilities of computers changes over the years, the standard does not set values, but properties
  • A short is at least as big as a char
  • A int is at least as big as a short
  • And so on.
• And you can find get constants for the max values

  • #include <climits> 

  • Look at /usr/include/limits.h
  • Look at /usr/include/c++/12/climits
• Take a look at intDemo.cpp
• When you go beyond the size it is called integer overflow
  • And sometimes integer underflow
• Take a look at intDemo.cpp