ssrs data matrix l l l in Software

Making QR Code ISO/IEC18004 in Software l l l

char middleInitial; unsigned maxUnsignedInt;

These names are easier to read than middleini tial and maxunsignedint. As an alternative, some programmers use a underscore to simulate blanks, like this:

char middle-initial; unsigned max-unsigned-int;

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An integer is a whole number: 0, 1, -1, 2, -2, 3, -3, etc. An unsigned integer is an integer that is not negative: 0, 1, 2, 3, etc. C++ has the following nine integer types:

char signed char unsigned char short int int long int unsigned unsigned unsigned short int int long int

The differences between these nine types is the range of values that they allow. These ranges depend, to some extent, upon the computer system being used. For example on most DOS PCs, int ranges between the values -32,768 and 32,767, while on most UNIX workstations it ranges between the values -2,147,483,648 and 2,147,483,647. The int" part may be omitted from the type names short int, long int, unsigned short int, unsigned int,and unsigned

The program in the example below prints the ranges of all the integer types on your machine. These limits, named SCHAR -MIN, L O N G - MAX, etc., are constants stored in the header file c 1 imi t s . h>, so the following preprocessor directive

This program prints the limits to the ranges of the various integer types:

// Prints the constants stored in 1imits.h:

"minimum "maximum "minimum "maximum "minimum "maximum "minimum "maximum "minimum "maximum "maximum "maximum "maximum "maximum

char = ' cc CHAR-MIN CC endl; char = ' << CHAR-MAX cc endl; short = ' << SHRT-MIN << endl; short = ' cc SHRTJAX << endl; int = ' cc INT-MIN << endl; int = ' << INTJLAX CC endl; long = ' cc LONG-MIN << endl; long = 'I << LONG-MAX << endl; signed char = ' cc SCHAR MIN << endl; signed char = ' -cc SCHARJAX << endl; unsigned char = ' cc UCHARJAX << endl; unsigned short = ' c-c USHRTJAX << endl; << UINT-MAX << endl; unsigned = unsigned long = ' << ULONGJAX << endl;

return 0;

This output is from a UNIX workstation. It shows that, on this system, there are really only six distinct integer types:

range -128 to 127 (1 byte) range -32,768 to 32,767 (2 bytes) range -2,147,483,648 to 2,147,483,647 range 0 to 255 (1 byte) range 0 to 65,535 (2 bytes) range 0 to 4,294,967,295 (4 bytes)

(4 bytes)

You can tell, for example, that short integers occupy 2 bytes (16 bits) on this machine, because the

range 32,768 to 32,767 covers 65,536 = 216 possible values. (Recall that a byte is 8 bits, the standard storage unit for characters.)

On a PC running Borland C++, this program produces the same ranges except for int and unsigned which have

range -32,768 to 32,767 (2 bytes) range 0 to 65,535 (2 bytes)

An operator is a symbol that operates on one or more expressions, producing a value that can be assigned to a variable. We have already encountered the output operator << and the assignment operator =. Some of the simplest operators are the operators that do arithmetic: +, -, *, /, and %. These operate on integer types to produce another integer type: m + n produces the sum m plus n, m - n produces the difference m minus n, -n produces the negation of n, m*n produces the product m times n, m/n produces the integer quotient when m is divided by n, and m%n produces the integer remainder when m is divided by n. These six operators are summarized in the following table and illustrated in the example below.

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INTRODUCTION TO PROGRAMMING IN C++ ,

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