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CHAPTER 5 OPERATORS AND EXPRESSIONS

User’s Manual U15556EJ1V0UM

(1) Subscript operators

Postfix Operators

[ ] Subscript Operator

FUNCTION

The [ ] subscript operator specifies or refers to a single member of an array object. The array or expression “E1

[E2]” is evaluated as if it were “(*(E1+(E2)))”. In other words, the value of E1 is a pointer to the first member of

the array and E2 (if it is an integer) indicates the E2th member of E1 (counting from 0). With a multidimensional

array, as many subscript operators as the number of dimensions must be connected.

In the following example, x becomes an int type array of 3*5. In other words, x is an array which has three

members each consisting of five int type members.

int x[3][5] ;

A multidimensional array may be specified by connecting subscript operators. Assuming that E is an array of nth

dimension (where n

≥ 2) consisting of i*j*...*k, the array can be specified with n number of subscript operators. In

this case, E becomes a pointer to an array of (n – 1)th dimension consisting of j*...*k.

SYNTAX

postfix-expression [subscripted expression]

NOTE

A postfix expression must have a “.... pointer to object”.

The subscripted expression of an array must be

specified with integral type data. The result of the expression will become “.....” type.

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