Lecture 8 increment_and_decrement_operators

Lecture 8 increment_and_decrement_operators

• 1.
  Increment and DecrementOperators www.eshikshak.co.in
• 2.
  Increment Operator (++) ● The increment operator (++) adds 1 to its operand. ● It is an unary operator ( A operator that requires only one operand is known as unary operator ) ● Auto-increment ● i++ add 1 to i ● i = i + 1 can be represented in two forms as 1) i += 1 2) i++ ● k = 2 * i++ ( means ``take i's old value and multiply it by 2, increment i, store the result of the multiplication in k'' ) www.eshikshak.co.in
• 3.
  Decrement Operator (--) ● The decrement operator (++) subtract 1 from its operand. ● It is an unary operator ( A operator that requires only one operand is known as unary operator ) ● Auto-decrement ● i-- subtracts 1 from i ● i = i - 1 can be represented in two forms as 1) I -= 1 2) i-- ● k = 2 * i-- ( means ``take i's old value and multiply it by 2, decrement i, store the result of the multiplication in k'' ) www.eshikshak.co.in
• 4.
  Postfix and PrefixForms ● There are two forms for each of the operators: postfix and prefix ● The statement ++i (prefix form) increments i before using its value ● The statement i++ (postfix form) increments it after its value has been used. ● The postfix increment and decrement operators fetch the current value of the variable ● Store a copy of it in a temporary location. The compiler then increments or decrements the variable www.eshikshak.co.in
• 5.
  Postfix Forms -Example ● i = 5; j = i++; printf(“nj : %d and i : %d”, j, i); ● Output : j : 5 and I : 6 www.eshikshak.co.in
• 6.
  Postfix Forms -Example ● i = 5; j = i++; printf(“nj : %d and i : %d”, j, i); printf(“ni : %d”,i++); printf(“ni : %d”,i); ● Output : j : 5 and i : 6 i:6 i:7 www.eshikshak.co.in
• 7.
  Prefix Forms -Example ● i = 5; j = ++i; printf(“nj : %d and i : %d”, j, i); ● Output : j : 6 and i : 6 www.eshikshak.co.in
• 8.
  Prefix Forms -Example ● i = 5; j = ++i; printf(“nj : %d and i : %d”, j, i); printf(“ni : %d”,++i); printf(“ni : %d”,i); ● Output : j : 6 and i : 6 i:7 i:7 www.eshikshak.co.in
• 9.
  Precedence of Incrementand Decrement Operators ● The increment and decrement operators have the same precedence, but bind from right to left. So the expression ● --j++ s evaluated as --(j++) www.eshikshak.co.in
• 10.
  Precedence of Incrementand Decrement Operators - Examples the value of k in i then ● i=k--; /* Stores decrements k. */ ● J=i++; /* Stores the value of l in j then increments i. */ ● i=--k; /* Decrements k then stores the new value of k in i. */ ● j=++l; /* Increments l then stores the new value of l in j. */ www.eshikshak.co.in
• 11.
  www.eshikshak.co.in