Numeric Types

• There are two basic numeric types in c/c++
  • Integer types
  • Floating point or real number types.
• Integer types
  • int is the basic type.
    • This represents numbers between INT_MIN and INT_MAX
      • #include <climits> for these and all other constants in this section.
    • Unfortunately this is not fixed in the standard.
    • So as the hardware changes, this value can change with it.
    • See /usr/include/limits.h
    • This is the workhorse for integer types. Prefer this to others.
  • int can be modified by the following
    • signed and unsigned
      • signed is the default and is probably never needed.
        • It means the number can be positive or negative.
      • unsigned
        • means the values are 0 ≤ n ≤ UINT_MAX.
        • UINT_MAX is probably twice INT_MAX.
        • You use this when you need more positive numbers and your value can never be negative.
    • short or long
      • are essentially smaller and larger versions of an int.
      • Currently short is 16 bits and ling is 64 bits.
      • But this changes.
      • These are for special use.
      • Can be modified with signed and unsigned
      • Can be modifiers for int but that is not needed.
    • long long is a special that is as big as gets supported.
• The type char is also an integer type.
  • This is confusing at first.
  • Remember, everything is stored as a number.
  • Characters are stored as their ASCII representation.
  • Look at the ASCII table.
  • We can do math on char type.
  • But it is printed as the character, not the number.
  • We will look at this more later.