Basic Input - Output. Output functions printf() – is a library function that displays information on-screen. The statement can display a simple text message. - презентация

1 Basic Input - Output

2 Output functions printf() – is a library function that displays information on-screen. The statement can display a simple text message or a message and the value of one or more program variables printf() – is a library function that displays information on-screen. The statement can display a simple text message or a message and the value of one or more program variables gotoxy() – positions the cursor on a specific location on the screen gotoxy() – positions the cursor on a specific location on the screen clrscr() – clears the screen and place the cursor at the upper left hand portion of the screen clrscr() – clears the screen and place the cursor at the upper left hand portion of the screen

3 Input functions scanf() – reads data from the keyboard according to a specified format and assigns the input data to one or more program variables. For numeric variables, the address can be passed by the address of operator, the ampersand (&) that is placed at the beginning of the variable name. scanf() – reads data from the keyboard according to a specified format and assigns the input data to one or more program variables. For numeric variables, the address can be passed by the address of operator, the ampersand (&) that is placed at the beginning of the variable name. getch() / getche() – gets a character from the keyboard. It waits until a key is pressed and then returns the inputted character to the calling function. Unlike the scanf() function, getch/e() does not wait for the carriage return key to be pressed. getch() / getche() – gets a character from the keyboard. It waits until a key is pressed and then returns the inputted character to the calling function. Unlike the scanf() function, getch/e() does not wait for the carriage return key to be pressed. The difference between the getch() and getche() is that the latter echoes the typed character to the screen.

4 Escape Sequences \ \rcarriage return \nnewline \tmove to the next tab \abeep the speaker \bbackspace prints single quote \prints double quote \\prints backslash character \xddprints character whish is in hexadecimal form

5 Format Specifier % %ccharacter %sstring %dinteger %ffloat %eexponential %xhexadecimal %ooctal %ldlong integer %lflong float / double precision

6 Declaration of Variables A variable is a named data storage location in your computers memory. Variables in C can contain letters, digits and the underscore character ( _ ). It should be remembered that C language is case sensitive; two similar words in different cases generate two different variables. A variable declaration tells the compiler the name and type of a variable and optionally initializes the variable to a specific value. When a variable is declared, the compiler sets aside a storage space for the variable.

7 Variable Type Keyword Bytes Required Range Characterchar to 127 Integerint to Long integer iong int to Floatfloat4 1.2E-38 to 3.4E38 Double precision double8 2.2E-308 to 1.8E308