++ Operator

Increment ++ and Decrement – Operator as Prefix and Postfix¶

In programming (Java, C, C++, JavaScript etc.), the increment operator ++ increases the value of a variable by 1. Similarly, the decrement operator -- decreases the value of a variable by 1.

a = 5
++a;          // a becomes 6
a++;          // a becomes 7
--a;          // a becomes 6
a--;          // a becomes 5

Simple enough till now. However, there is an important difference when these two operators are used as a prefix and a postfix.

++ and – operator as prefix and postfix¶

• If you use the ++ operator as a prefix like: ++var, the value of var is incremented by 1; then it returns the value.
• If you use the ++ operator as a postfix like: var++, the original value of var is returned first; then var is incremented by 1.

The -- operator works in a similar way to the ++ operator except -- decreases the value by 1.

Let’s see the use of ++ as prefixes and postfixes in C, C++, Java and JavaScript.

Example:¶

#include <stdio.h>
int main() {
   int var1 = 5, var2 = 5;

   // 5 is displayed
   // Then, var1 is increased to 6.
   printf("%d\n", var1++);

   // var2 is increased to 6 
   // Then, it is displayed.
   printf("%d\n", ++var2);

   return 0;
}