Increment and Decrement Operators

Increment and Decrement Operators Adding or subtracting 1 from a variable is a very common programming practice.  Adding 1 to a variable is calledincrementing and subtracting 1 from a variable is calleddecrementing. Increment and decrement operators work only with integer variables -- not on floating point variables or literals. The C++ compiler is controlling the execution of the prefix and postfix operators.  You cannot change this order of execution.  For example, the parentheses below will not force an early execution: value = (((x--)))* num;   //still decrements x last. One disadvantage of using the increment/decrement operators is that the variable can only be incremented or decremented by the value ONE.  If you need to increment (or decrement) by a larger (or smaller) value, you must use statements like  m += 2;  or  amount -= 5; Be careful when combining increment and decrement operators inside expressions with logical operators.  If in doubt, don't use them together.  For example, do NOT use: if (( num1 = = 4 ) || ( num2 != ++j)) (j may not be incremented when (num1 = = 4) is TRUE.)Instead, separate the code to avoid this problem: ++j; if (( num1 = = 4) || (num2 != j))

All are the same:i = i + 1;  i += 1; i++; Prefix:  ++i; --i;increment or decrement occurs before the variable's value is used in the remainder of the expression. Postfix: i++; i--;increment or decrement occurs after the variable's value is used in the remainder of the expression.

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