Increment and Decrement Operator in C
#Increment Operators are used to increased the value of the variable by one and Decrement Operators are used to decrease the value of the variable by one in C programs.
Both increment and decrement operator are used on a single operand or variable, so it is called as a unary operator. Unary operators are having higher priority than the other operators it means unary operators are executed before other operators.
Syntax
++ // increment operator -- // decrement operator
Note: Increment and decrement operators are can not apply on constant.
Example
x= 4++; // gives error, because 4 is constant
Type of Increment Operator
- pre-increment
- post-increment
pre-increment (++ variable)
In pre-increment first increment the value of variable and then used inside the expression (initialize into another variable).
Syntax
++ variable;
Example pre-increment
#include<stdio.h> #include<conio.h> void main() { int x,i; i=10; x=++i; printf("x: %d",x); printf("i: %d",i); getch(); }
Output
x: 11 i: 11
In above program first increase the value of i and then used value of i into expression.
post-increment (variable ++)
In post-increment first value of variable is used in the expression (initialize into another variable) and then increment the value of variable.
Syntax
variable ++;
Example post-increment
#include<stdio.h> #include<conio.h> void main() { int x,i; i=10; x=i++; printf("x: %d",x); printf("i: %d",i); getch(); }
Output
x: 10 i: 11
In above program first used the value of i into expression then increase value of i by 1.
Type of Decrement Operator
- pre-decrement
- post-decrement
Pre-decrement (-- variable)
In pre-decrement first decrement the value of variable and then used inside the expression (initialize into another variable).
Syntax
-- variable;
Example pre-decrement
#include<stdio.h> #include<conio.h> void main() { int x,i; i=10; x=--i; printf("x: %d",x); printf("i: %d",i); getch(); }
Output
x: 9 i: 9
In above program first decrease the value of i and then value of i used in expression.
post-decrement (variable --)
In Post-decrement first value of variable is used in the expression (initialize into another variable) and then decrement the value of variable.
Syntax
variable --;
Example post-decrement
#include<stdio.h> #include<conio.h> void main() { int x,i; i=10; x=i--; printf("x: %d",x); printf("i: %d",i); getch(); }
Output
x: 10 i: 9
In above program first used the value of x in expression then decrease value of i by 1.
Example of increment and decrement operator
Example
#include<stdio.h> #include<conio.h> void main() { int x,a,b,c; a = 2; b = 4; c = 5; x = a-- + b++ - ++c; printf("x: %d",x); getch(); }
Output
x: 0
