contents   index   previous   next

Auto-increment (++) and auto-decrement (--)

To add or subtract one, 1, to or from a variable, use the autoincrement, ++, or autodecrement, , operator. These operators add or subtract 1 from the value to which they are applied. Thus, i++ is a shortcut for i += 1, which is a shortcut for i = i + 1.


These operators can be used before, as a prefix operator, or after, as a postfix operator, their variables. If they are used before a variable, it is altered before it is used in a statement, and if used after, the variable is altered after it is used in the statement. The following lines demonstrates prefix and postfix operations.


i = 4;

i is 4

j = ++i;

j is 5, i is 5

(i was incremented before use)

j = i++;

j is 5, i is 6

(i was incremented after use)

j = --i;

j is 5, i is 5

(i was decremented before use)

j = i--;

j is 5, i is 4

(i was decremented after use)


i is 5

(i was incremented)


Bit operators