Integer Math

• + and - are as expected.
  • But because of the way things are implemented it "wraps around"
  • INT_MAX+1
  • INT_MIN-1
  • Look at intDemo.cpp
    • Notice this produces a warning:
    • 
    • Warnings: fix them, do not ignore them.
  • This is called numeric overflow
• * is multiply
  • Nothing different here.
  • But it can produce numeric overflow.
• / is divide
  • This is a bit strange.
  • It does integer division.
  • Or only looks at the integer part
  • Remember long division
  • 23/4 = 5 R 3
  • in c++ 23/4 = 5
  • in c++ 2/4 = 0
• % is modulus
  • This the the remainder.
  • 23%4 = 3
  • 2 %4 = 2
  • This is really useful some times.
• ++ and --
  • we write a = a + 1 quite a bit.
  • So a++ is a shortcut.
  • ++a is also a shortcut.
  • But be aware, there are difference.
  • Just use them on a line by themselves and they are fine.
  • -- is the same as a = a -1
• Some other shortcuts.
  • a += 4 is the same as a = a + 4
  • This is true for many operators.
• The order of operations you learned in math applies.
  • Please excuse my dear aunt sally
  • Use () like you did in math.