What is the difference between = and == operators in C

What is the difference between “=” and “==” operators in C

  • First of all = is a assignment operator and == is a comparison operator.
  • = operator is used to assign value to a variable and == operator is used to compare two variable or constants.
  • The left side of = operator can not be a constant, while for == operator both sides can be operator.

What is the difference between pre increment operator(++var) and post increment operator(var++).

Pre increment operator(++var) first increment the value of variable by one and then it returns its value whereas post increment operator (var++) first returns the value of variable then increments its value by 1.

For Example :

int var = 2;
printf("%d", ++var);

Pre increment operator first increment the value of var to 3 and then returns its value. Above printf statement will print 3. Let. int var = 2;
printf(“%d”, var++);
Post increment operator first returns the value of var and then increments its value by one. Above printf statement will print 2 and value of var becomes 3.

What is the difference between pre decrement operator(–var) and post decrement operator(var–).

Pre decrement operator(–var) first decrement the value of variable by one and then it returns its value whereas post decrement operator (var–) first returns the value of variable then decrements its value by 1.

For Example :

printf("%d", --var);

Pre decrement operator first decrement the value of var by one and then returns its value. Above printf statement will print 1.
int var = 2;
printf(“%d”, var–);

Post decrement operator first returns the value of var and then decrement its value by one. Above printf statement will print 2 and value of var becomes 1.